Smoking device

ABSTRACT

Apparatus and methods are described for use with a portion of plant material that includes at least one active ingredient. A vaporizing unit includes a heating element configured to heat the plant material, and a sensor configured to detect an indication of airflow rate through the vaporizing unit. Control circuitry is configured to receive an indication of the airflow rate through the vaporizing unit, and, in response thereto, to determine a smoking profile that is desired by the user. The control circuitry drives the heating element to vaporize the active ingredient of the plant material by heating the plant material according to the determined smoking profile. The control circuitry dynamically updates the smoking profile in response to changes in airflow rate over the course of a smoking session. Other applications are also described.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation under 35 U.S.C. § 120 of U.S.application Ser. No. 16/333,446, filed Mar. 14, 2019, which is anational phase under 35 U.S.C. § 371 of International Application No.PCT/IL2017/051041, filed Sep. 14, 2017, which claims priority to U.S.Provisional Application No. 62/394,243, filed Sep. 14, 2016, U.S.Provisional Application No. 62/453,544, filed Feb. 2, 2017, U.S.Provisional Application No. 62/500,509, filed May 3, 2017, and U.S.Provisional Application No. 62/525,773, filed Jun. 28, 2017, the entirecontents of each of which are hereby incorporated by reference.

FIELD

Some applications of the present invention generally relate to a smokingapparatus. Specifically, some applications of the present inventionrelate to smoking devices for the delivery of an active ingredient to asubject.

BACKGROUND

Mouthfullness is an attribute that smokers refer to that relates to thetexture and feel of tobacco smoke in the mouth. In order to reproducethe taste and feel of tobacco smoke, electronic cigarettes typicallyheat tobacco plant material or other non-liquid materials containingactive ingredients (e.g., nicotine). The active ingredients are releaseddue to the application of heat on the material.

Medical use of cannabis and its constituent cannabinoids, such astetrahydrocannabinol (THC) and cannabidiol (CBD), has a long history. Inmodern times, cannabis is used by patients suffering from AIDS, orundergoing chemotherapy treatment, in order to relieve nausea andvomiting associated with their conditions. Cannabis is also used in amedicinal manner in order to provide pain relief, to treat musclespasticity, and to stimulate appetite.

Medicinal cannabis can be administered using a variety of methods,including vaporizing or smoking dried buds, eating extracts, takingcapsules or using oral sprays. The legality of medical use of cannabisvaries internationally. However, even in countries in which the medicaluse of cannabis is legal, the provision of cannabis to such users ishighly regulated, and it is the case that in almost all Westerncountries, recreational use of cannabis is illegal.

SUMMARY

In accordance with some applications of the present invention, a smokingdevice is used to vaporize the active ingredient of a material, such asa plant material, by heating the material. For example, the smokingdevice may be used to vaporize tobacco, cannabis, and/or other plant orchemical substances that contain an active ingredient (such as nicotine,tetrahydrocannabinol (THC) and/or cannabidiol (CBD)) that becomesvaporized upon the substance being heated. In general, the materialcontaining the active ingredient is described herein as being a plantmaterial. However, the scope of the present application includes using anon-plant material, such as synthetic materials that contain activeingredients, as an alternative or in addition to the plant material.

Typically, the smoking device includes a vaporizing unit, and areloading unit. The reloading unit houses a plurality of capsules, eachof the capsules including a given amount of a plant material thatcontains an active ingredient. For some applications, the reloading unitis shaped to define first and second receptacles, each of which isshaped to house the plurality of capsules in stacked configurations.While each of the capsules is disposed at a vaporization location withinthe vaporizing unit, a heating element causes the active ingredient ofthe plant material within the capsule to become at least partiallyvaporized by individually heating the capsule. For some applications,the heating element includes one or more electrodes that heat thecapsule via resistive heating, by driving a current into a portion ofthe capsule (e.g., into a metallic mesh of the capsule). Alternativelyor additionally, a current is driven into an internal heating elementthat is housed within the vaporizing unit, and the internal heatingelement heats the capsule via conductive heating. Typically, acapsule-loading mechanism of the reloading unit individually transferseach of the capsules from the first receptacle in the reloading deviceto the vaporization location in the vaporizing unit and from thevaporization location to the second receptacle within the reloadingunit. For some applications, the smoking device includes the vaporizingunit in the absence of the reloading unit. For example, the vaporizingunit may be configured such that a user can insert individual capsulesinto the vaporizing unit, and can then use the vaporizing unit tovaporize the active ingredient of the plant material.

For some applications, the vaporizing unit of the smoking device isconfigured such that various different types of capsules can be usedwith the vaporizing unit. For example, respective types of capsules maycontain different quantities of plant material, plant materialcontaining different amount of active ingredients, and/or differenttypes of plant materials. Alternatively or additionally, respectivetypes of capsules may have respective characteristics, e.g., respectiveflavors, strengths, richnesses, active ingredients, etc. For someapplications, control circuitry of the vaporizing unit is configured toadjust a heating profile of the capsules to the capsule type that iscurrently being heated. For some such applications, the controlcircuitry implements an automatic capsule classification procedure, inaccordance with which the control circuitry automatically classifies thecapsule that is currently being heated as a given type of capsule, anddesignates a capsule heating profile accordingly.

Typically, the vaporizing unit is configured to replicate the responsesof a traditional combustible cigarette to the manner in which a smokersmokes the cigarette. For example, when a traditional combustioncigarette is smoked, the cigarette undergoes an increased heating andburning rate in response to the smoker inhaling more strongly, and theresultant increased airflow through the cigarette. For someapplications, in order to replicate this effect, the vaporizing unitapplies a variable-temperature heating process to the plant material,for example, in the following manner. Typically, in response toreceiving a first input at the vaporizing unit, the heating process isinitiated and the plant material is heated above ambient temperature. Anindication of the airflow rate through the vaporizing unit (e.g., theairflow rate through the capsule is which the plant material isdisposed) is then measured. For example, the airflow rate may bemeasured directly by an airflow or pressure gauge. Alternatively oradditionally, an indication of the airflow rate may be measuredindirectly, by detecting an indication of the temperature of the plantmaterial, e.g., by measuring the temperature of the capsule using atemperature sensor. For some applications, a temperature sensor is usedthat is configured to measure the temperature of the capsule withoutdrawing heat from the capsule, as described in further detailhereinbelow. By measuring the temperature of the capsule in this manner,the measured temperature is typically more accurate than is thetemperature sensor were to measure the temperature of the capsule inmanner that draws heat from the capsule, ceteris paribus. Furthermore,the temperature sensor typically has a “near zero” response time, suchthat the control circuitry is able to measure changes in temperature dueto changes in airflow, and respond to such changes in the mannerdescribed hereinbelow, effectively immediately with respect to theperception of the user. For example, the temperature sensor may beconfigured to detect changes in temperature within 0.01 seconds, e.g.,within 1 millisecond, of such changes. For some applications, by virtueof having such a temperature sensor, the control circuitry is configuredto respond to airflow-induced changes in temperature within 0.01seconds, e.g., within 1 millisecond, of such changes.

Since the plant material is heated above ambient temperature, in theabsence of heating being applied to the capsule, airflow through thecapsule would cool the capsule by inducing forced heat transfer byconvection. Thus, the induced heat transfer is indicative of the airflowrate through the capsule. Therefore, for some applications, based on thedetected temperature indication, control circuitry of the vaporizingunit drives the heating element to maintain the temperature of thecapsule constant, and measures the electrical power needed to maintainthe temperature of the capsule constant. The electrical power that isneeded to maintain the temperature of the capsule constant indicates thepower required to overcome heat loss due to airflow through the capsule,and is therefore indicative of airflow through the capsule.Alternatively, the capsule is not maintained at a constant temperature,and the control circuitry determines the rate of airflow through thecapsule based on a measured change in the temperature of the capsule.For example, the control circuitry may continue to heat the capsule at afixed power, and measure the changes in temperature of the capsule.Typically, such changes in temperature are indicative of the airflowrate through the capsule. Alternatively, the control circuitry may stopheating the capsule when the capsule is at a given temperature, andmeasure changes in the temperature of the capsule. Typically, suchchanges in temperature are correlated with the rate of airflow throughthe capsule.

In response to the measured indication of the airflow rate, the controlcircuitry typically determines a smoking profile that is desired by theuser and heats the plant material according to the determined smokingprofile. A target temperature for the capsule is typically determined asa function of the measured indication of airflow rate. Typically, thetarget temperature increases as a function of an increase in airflowrate. Further typically, a maximal target temperature will be limited toa predefined maximum value in order not to exceed safety limits, and/orin order not to generate a bad taste due to overheating the plantmaterial. In response to detecting an indication that the temperature ofthe capsule has reached the target temperature, further heating of thecapsule is withheld. Subsequently, in response to receiving a furtherindication of the airflow rate, the control circuitry determines anupdated smoking profile that is desired by the user. Typically, a newtarget vaporization temperature is defined according to the updatedsmoking profile. Typically, over the course of a smoking session, inresponse to receiving ongoing airflow measurements, the controlcircuitry dynamically determines smoking profiles that are desired bythe user, and adjusts the heating of the capsule accordingly. For someapplications, the target temperature to which the plant material isheated is dynamically updated in order to adjust the vaporizationtemperature and vaporization rate according to the desired smokingprofile of the user. For some applications, the target temperature towhich the plant material is heated is dynamically updated in acontinuous manner. Alternatively, the target temperature to which theplant material is heated is dynamically updated on a puff-by-puff basis,i.e., with each inhalation of the user, the control circuity calculatesa target temperature to which the capsule should be heated for thatinhalation. For some applications, each inhalation of the user isdetected automatically by detecting airflow through the capsule, inaccordance with the techniques described herein.

Typically, the control circuitry employs various heating profiles inorder to simulate the behavior of a standard combustion cigarette, andin order to accommodate the user's indicated desired smoking profile, aswell as the type of plant material that is used. For some applications,one or more of the following functionalities are provided by avaporizing unit that dynamically adjusts the heating of the plantmaterial in response to a measured airflow rate indication, as describedhereinabove:

1) When smoking a traditional combustion cigarette, an increase in theuser's inhalation rate increases generated smoke due to intensificationof cigarette flame. In addition, the temperature of the inhaled smoke istypically greater. Therefore, for some applications, the targettemperature to which the capsule is heated is correlated to airflow rate(which is indicative of user inhalation rate), in order to simulate theburning of a traditional cigarette as described above. As describedhereinabove, typically the capsule is not heated above a predefinedmaximal temperature limit. Typically, the predefined maximal temperaturelimit is set such that the plant material is not heated to a temperaturethat is greater than the pyrolysis temperature of the plant material,and/or such that the plant material is not heated to a temperature thatwill produce smoke and/or a bad taste. By dynamically adjusting thetarget vaporization temperature as described hereinabove, the taste and“mouthfullness” of the generated vapors are adjusted according to user'sindividual taste and preferences. For example, users that prefer a longand slow inhalation will benefit from receiving a constant slow supplyof the vaporized active ingredient, due to the relatively lowervaporization temperature that will be generated by the lower airflowrate of the slow inhalation. On the other end, users that prefer afaster and more intense release of the active ingredient will enjoy thehigher rate of active ingredient vaporization rate that will result fromthe higher vaporization temperature to which the plant material isheated, due to their elevated inhalation airflow rate.

2) Dynamically adjusting the target temperature to which the plantmaterial is heated as described hereinabove, may provide higherefficiency in the consumption rate of the plant material. For example,users that prefer taking several relatively short puffs will not sufferfrom loss of plant material between the short puffs, since the controlcircuitry will lower the target temperature to which the capsule isheated between the puffs.

3) Dynamically adjusting the target temperature to which the capsule isheated as described hereinabove, may reduce loss of active ingredientprior to the beginning of user inhalation. The lack of airflow prior tothe user's inhalation will result in the target temperature to which thecapsule is heated being relatively low, such as to reduce vaporizationof active ingredient prior to user inhalation.

4) In some cases, a delivery of a constant dose of the active ingredientis desired on every puff. For a given arrangement of plant material, themass of the active ingredient that is vaporized is a function of, atleast, the temperature of the material and of the airflow rate throughthe material. For some applications, an airflow-related heating processis used as described hereinabove, and the control circuitry responds tothe measured airflow indication, such as to deliver a constant dose ofthe active ingredient for each puff of the vaporizing unit. For example,a function may be used in accordance with which the vaporizationtemperature is reduced in response to the airflow increasing.

5) For some applications, the control circuitry additionally accountsfor the amount of active ingredient that has already been vaporized fromthe portion of the plant material that is currently being heated (whichmay, for example, be a portion of the plant material that is disposedinside a capsule). For example, in some cases, based on the rates ofairflow and temperatures that have already been applied to the capsulethat is currently being heated, the control circuitry may determine anamount of the active ingredient that has already been vaporized. Forsome applications, the control circuitry determines the targettemperature to which to heat the capsule, in response to the amount ofactive ingredient that has already been vaporized. For someapplications, the control circuitry determines the target temperature towhich to heat the capsule, in response to (a) the amount of activeingredient that has already been vaporized, as well as (b) the currentmeasured airflow through the vaporizing unit (e.g., through the plantmaterial that is being heated within the vaporizing unit). For example,for a given airflow rate, the control circuitry may heat the capsule toa greater temperature, the greater the amount of the active ingredientthat has already been vaporized. This may be because, once a givenamount of the active ingredient has already been vaporized from theplant material, the plant material may need to be heated to a greatertemperature in order for the remaining active ingredient to bevaporized. For some applications, in response to determining that agiven amount of the active ingredient has already been released from theplant material, the control circuitry may be configured to reduce thetemperature of the plant material to a sub-vaporization temperature,such as to withhold additional vaporization of active ingredient.

It is noted that some applications of the present invention aredescribed with reference to tobacco. However, the scope of the presentinvention includes using any material or substance that contains anactive ingredient, mutatis mutandis.

In accordance with some applications of the present invention, avaporizer is used to vaporize the active ingredient of a material, suchas a plant material, by heating the material. For example, the vaporizermay be used to vaporize the constituent cannabinoids of cannabis (e.g.,tetrahydrocannabinol (THC) and/or cannabidiol (CBD)). Alternatively oradditionally, the vaporizer may be used to vaporize tobacco, and/orother plant or chemical substances that contain an active ingredientthat becomes vaporized upon the substance being heated.

There is therefore provided, in accordance with some applications of thepresent invention, apparatus for use with a portion of plant materialthat includes at least one active ingredient, the apparatus including:

a vaporizing unit comprising:

-   -   a heating element configured to heat the plant material;    -   a sensor configured to detect an indication of airflow rate        through the vaporizing unit that is generated by a user; and    -   control circuitry configured:        -   to receive a first indication of the airflow rate through            the vaporizing unit from the sensor;        -   in response to receiving the first indication of the airflow            rate, to determine a first smoking profile that is desired            by the user; and        -   to drive the heating element to vaporize the active            ingredient of the plant material by heating the plant            material according to the determined smoking profile; and        -   subsequently:            -   to receive a further indication of the airflow rate                through the vaporizing unit from the sensor; and            -   in response to receiving the further indication of the                airflow rate, to determine an updated smoking profile                that is desired by the user; and            -   to drive the heating element to vaporize the active                ingredient of the plant material by heating the plant                material according to the determined updated smoking                profile.

In some applications, the control circuitry:

is further configured to measure an amount of heating that the portionof the plant material has already undergone, and

is configured to drive the heating element to vaporize the activeingredient of the plant material by heating the plant material accordingto the determined smoking profile by determining a temperature to whichto heat the portion of the plant material at least partially based uponthe measured indication of the airflow rate and the amount of heatingthat the portion of the plant material has already undergone.

In some applications, the control circuitry is configured:

in response to receiving an indication of the airflow rate through thevaporizing unit from the sensor, to determine that the user is notinhaling from the vaporizing unit, and

in response thereto, to drive the heating element to reduce heating ofthe plant material, such that a temperature of the plant materialdecreases below a vaporization temperature of the active ingredient.

In some applications, the sensor includes a temperature sensorconfigured to detect an indication of a temperature of the plantmaterial, and the control circuitry is configured to calculate a rate ofairflow through the vaporizing unit, based upon the indication of thetemperature of the plant material measured by the temperature sensor. Insome applications, the control circuitry is configured to calculate therate of airflow through the vaporizing unit by detecting an indicationof an amount of energy required to maintain the temperature of the plantmaterial constant. In some applications, the control circuitry isconfigured to calculate the rate of airflow through the vaporizing unitby detecting an indication of a change in the temperature of the plantmaterial that is caused by heat transfer from the plant material toambient air that passes through the capsule. In some applications, thecontrol circuitry is configured to receive an indication of ambienttemperature, and to calculate the rate of airflow through the vaporizingunit, by accounting for a difference between the temperature of theplant material and the ambient temperature.

In some applications, the temperature sensor is configured to detect achange in the temperature of the plant material within 0.01 second ofthe change occurring. In some applications, the temperature sensor isconfigured to detect the temperature of the plant material withoutdrawing heat from the plant material. In some applications, thetemperature sensor includes an optical temperature sensor. In someapplications, the temperature sensor includes an infrared temperaturesensor. In some applications, the apparatus further includes a capsuleconfigured to house the portion of plant material, and the temperaturesensor is configured to detect the indication of the temperature of theplant material by detecting a temperature of the capsule. In someapplications, the temperature sensor is configured to detect theindication of the temperature of the plant material by detectingelectrical resistance of at least a portion of the capsule.

In some applications, during a smoking session, the control circuitry isconfigured to dynamically respond to changes in the user's inhalationby:

receiving indications of the airflow rate through the vaporizing unitfrom the sensor;

in response to receiving the indications of the airflow rate,determining updated smoking profiles that are desired by the user; and

driving the heating element to vaporize the active ingredient of theplant material by heating the plant material according to the determinedupdated smoking profiles.

In some applications, during the smoking session, the control circuitryis configured to dynamically respond to changes in the user'sinhalation, on a puff-by-puff basis. In some applications, in responseto receiving that airflow rate through the vaporizing unit hasincreased, the control circuitry is configured to drive the heatingelement to allow a temperature of the plant material to decrease. Insome applications, during a smoking session, the control circuitry isconfigured to dynamically respond to changes in the user's inhalation,on a continuous basis. In some applications, during a smoking session,the control circuitry is configured to dynamically respond to changes inthe user's inhalation, within 0.01 seconds of changes in airflow ratethrough the vaporizing unit that are generated by the user's inhalation.

In some applications, in response to receiving an indication from thesensor that airflow rate through the vaporizing unit has increased, thecontrol circuitry is configured to drive the heating element to increasea temperature of the plant material. In some applications, the controlcircuitry is configured to withhold the heating element from heating theplant material above a given threshold temperature.

In some applications, the control circuitry is configured to determine aclassification of the plant material, and at least partially in responsethereto, to determine the first smoking profile and the updated smokingprofile. In some applications, based upon the classification of theplant material, the control circuitry is configured to determine amanner in which to vary a temperature to which to drive the heatingelement to heat the plant material, in response to changes in theairflow through the vaporizing unit. In some applications, the plantmaterial is housed inside a capsule, and the control circuitry isconfigured to determine the classification of the plant materialautomatically by measuring a characteristic of the capsule.

There is further provided, in accordance with some applications of thepresent invention, a method for use with a vaporizing unit that isconfigured to vaporize at least one active ingredient of a portion of aplant material, the method including:

measuring an indication of airflow rate through the vaporizing unitgenerated by a user;

in response to the measured indication of the airflow rate, determininga smoking profile that is desired by the user;

vaporizing the at least one active ingredient of the plant material byheating the plant material according to the determined smoking profile;

subsequently:

-   -   receiving a further indication of airflow rate through the        vaporizing unit generated by the user; and    -   in response to receiving the further indication of the airflow        rate, determining an updated smoking profile that is desired by        the user; and    -   vaporizing the at least one active ingredient of the plant        material by heating the plant material according to the        determined updated smoking profile.

There is further provided, in accordance with some applications of thepresent invention, apparatus including:

a vaporizer comprising:

-   -   at least one capsule comprising:        -   a material containing at least one active ingredient; and        -   covering layers configured to cover the material; and    -   control circuitry configured to:        -   vaporize the at least one active ingredient of the material            by heating the capsule;        -   classify the capsule as a given type of capsule; and        -   configure the heating of the capsule based upon the            classification of the capsule.

In some applications, the covering layers of the capsule include meshes.In some applications, the covering layers of the capsule includeperforated sheets. In some applications, the material includes a plantmaterial selected from the group consisting of: cannabis, and tobacco.

In some applications, the control circuitry is configured:

to measure an indication of airflow rate through the vaporizer, and

based upon the classification of the capsule, to determine a manner inwhich to vary a temperature to which to heat the material, in responseto changes in the airflow through the vaporizer.

In some applications, at least a portion of the capsule is colored, andthe control circuitry is configured to classify the capsule as the giventype of capsule by detecting the color of the portion of the capsule. Insome applications, the capsule is at least partially coated with acoating that includes a material that has a predefined thermalemissivity, and the control circuitry is configured to classify thecapsule as the given capsule type, by determining the thermal emissivityof the coating. In some applications, at least a portion of the capsulehas a predefined electrical resistance, and the control circuitry isconfigured to categorize the capsule as the given capsule type, bymeasuring the electrical resistance of the portion of the capsule.

In some applications, the capsule is thermally coupled to at least onephase-change material and the control circuitry is configured toclassify the capsule as the given type of capsule by detecting aphase-change temperature of the phase-change material. In someapplications, the capsule is thermally coupled to a plurality ofphase-change materials, and the control circuitry is configured toclassify the capsule as the given type of capsule by detectingrespective phase-change temperatures of the plurality of phase-changematerials. In some applications, the control circuitry is furtherconfigured to detect whether the capsule was previously used bydetecting the phase-change material.

There is further provided, in accordance with some applications of thepresent invention, a method including:

placing into a vaporizer at least one capsule, the capsule includingcovering layers, and material housed within the capsule, the materialcontaining at least one active ingredient; and

activating control circuitry configured to:

-   -   vaporize the at least one active ingredient of the material by        heating the capsule;    -   classify the capsule as a given type of capsule; and    -   configure the heating of the capsule based upon the        classification of the capsule.

The present invention will be more fully understood from the followingdetailed description of embodiments thereof, taken together with thedrawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of the exterior of a smoking device,in accordance with some applications of the present invention;

FIG. 2 is a schematic illustration of the exterior of a reloading unitof the smoking device of FIG. 1 , in accordance with some applicationsof the present invention;

FIG. 3 is a schematic illustration of the exterior of a vaporizing unitof the smoking device of FIG. 1 , in accordance with some applicationsof the present invention;

FIG. 4A is a schematic illustration of the exterior of a capsule thatcontains an active ingredient, in accordance with some applications ofthe present invention;

FIG. 4B is a cross-sectional view of the capsule of FIG. 4A, inaccordance with some applications of the present invention;

FIG. 4C is a schematic illustration of a capsule that includesperforated sheets, in accordance with some applications of the presentinvention;

FIGS. 4D and 4E are schematic illustrations of meshes or perforatedsheets of a capsule, in accordance with some applications of the presentinvention;

FIG. 4F is a schematic illustration of a capsule that is provided to auser with plant material within the capsule covered by non-perforatedsheets, in accordance with some applications of the present invention;

FIG. 5 is a schematic illustration of the exterior of a vaporizing unitand a capsule aligned for insertion into the vaporizing unit, inaccordance with some applications of the present invention;

FIG. 6 is a cross-sectional view of the vaporizing unit of FIG. 3 , inaccordance with some applications of the present invention;

FIG. 7 is a schematic illustration of a portion of a vaporizing unit ofFIG. 3 with a capsule disposed at a vaporization location within thevaporizing unit, in accordance with some applications of the presentinvention;

FIGS. 8A, 8B, and 8C are schematic illustrations of respective cut-awayviews of a smoking device that includes a vaporizing unit placed in areloading unit, at respective stages of the operation of acapsule-loading mechanism, in accordance with some applications of thepresent invention;

FIG. 9A, 9B, and 9C are respective cross-sectional views of a smokingdevice that includes a vaporizing unit placed in a reloading unit, atrespective stages of the operation of a capsule-loading mechanism, inaccordance with some applications of the present invention;

FIG. 10 is a graph illustrating a technique for heating a capsule thatcontains plant material containing an active ingredient, in accordancewith some applications of the present invention;

FIG. 11 is a graph illustrating heating curves of capsules containingphase-change materials with different phase-change temperatures, inaccordance with some applications of the present invention;

FIG. 12A is a graph illustrating a technique for heating plant materialusing a vaporizer, in accordance with some applications of the presentinvention;

FIG. 12B is a graph illustrating a technique for heating plant materialusing a vaporizer, in accordance with some applications of the presentinvention;

FIG. 13 is a schematic illustration of a vaporizer that is configured toautomatically extract a given volumetric dose of a plant material from amass of the plant material that is disposed in a receptacle of thevaporizer, in accordance with some applications of the presentinvention;

FIG. 14 is a schematic illustration showing an exploded view of thevaporizer of FIG. 13 , in accordance with some applications of thepresent invention;

FIG. 15 is a schematic illustration showing a three-dimensional view ofa rear side of the vaporizer of FIG. 13 , in accordance with someapplications of the present invention;

FIG. 16 is a schematic illustration showing a cross-sectional view ofthe vaporizer of FIG. 13 , in accordance with some applications of thepresent invention;

FIGS. 17A, 17B, 17C, 17D, and 17E are schematic illustrations showingcross-sectional views of an extraction mechanism of the vaporizer ofFIG. 13 , at respective stages of the operation of the extractionmechanism, in accordance with some applications of the presentinvention;

FIG. 18 is a schematic illustration of a vaporizer that is configured toautomatically extract a given volumetric dose of a plant material from amass of the plant material that is disposed in a receptacle of thevaporizer, in accordance with some applications of the presentinvention;

FIG. 19 is a schematic illustration showing an exploded view of thevaporizer of FIG. 18 , in accordance with some applications of thepresent invention;

FIG. 20 is a schematic illustration showing a cross-sectional view ofthe vaporizer of FIG. 18 , in accordance with some applications of thepresent invention;

FIG. 21 is a schematic illustration of an extraction mechanism of thevaporizer of shown in FIG. 18 , in accordance with some applications ofthe present invention;

FIGS. 22A and 22B are schematic illustrations of front and rear views ofthe extraction mechanism of the vaporizer of FIG. 18 , during a firststage of the operation of the extraction mechanism, in accordance withsome applications of the present invention;

FIGS. 23A and 23B are schematic illustrations of front and rear views ofthe extraction mechanism of the vaporizer of FIG. 18 , during a secondstage of the operation of the extraction mechanism, in accordance withsome applications of the present invention;

FIGS. 24A and 24B are schematic illustrations of front and rear views ofthe extraction mechanism of the vaporizer of FIG. 18 , during a thirdstage of the operation of the extraction mechanism, in accordance withsome applications of the present invention;

FIGS. 25 and 26 are schematic illustrations of a wiping element of thevaporizer of FIG. 18 , in accordance with some applications of thepresent invention; and

FIGS. 27A and 27B are bar charts showing the mass of active ingredientthat is released from plant material with respective, successive puffsof a vaporizer, in accordance with some applications of the presentinvention.

DETAILED DESCRIPTION

Reference is now made to FIGS. 1-3 , which are schematic illustrationsof the exterior of a smoking device 20, the smoking device including areloading unit 22 and a vaporizing unit 21, in accordance with someapplications of the present invention. Typically, smoking device 20 isused to vaporize the active ingredient of a material, such as plantmaterial. For example, smoking device 20 may be used to vaporize theconstituent cannabinoids of cannabis (e.g., tetrahydrocannabinol (THC)and/or cannabidiol (CBD)). Alternatively or additionally, the vaporizeris used to vaporize an active ingredient from tobacco (e.g., nicotine),and/or other plant or chemical substances that contain an activeingredient that becomes vaporized upon the substance being heated. It isnoted that some applications of the present invention are described withreference to a plant material that contains an active ingredient.However, the scope of the present invention includes using any substancethat contains an active ingredient (e.g., a synthetic substance thatcontains an active ingredient), mutatis mutandis. Smoking device 20 mayalternatively be referred to as a “smoking device” and/or as an“electronic cigarette,” and in the context of the present application,these terms should be interpreted as being interchangeable with oneanother. Similarly, in the context of the present application, the terms“vaporizing unit,” “vaporizer,” “electronic cigarette,” and “smokingpiece” should be interpreted as being interchangeable with one another.

For some applications, smoking device 20 includes a reloading unit 22and a vaporizing unit 21. For some applications, the reloading unithouses capsules 29, a capsule-loading mechanism 56, and a power supply45, as described in further detail herein below. For some applications,the vaporizing unit houses a vaporization location 54, an internal powersupply 33 and control circuitry 34. The control circuitry is configuredto act as a control unit, which controls the functioning of thevaporizing unit. Typically, the reloading unit and the vaporizing unitare reversibly couplable to each other. The smoking device isconfigured, such that in order to load a capsule into the vaporizingunit, and/or to discard a used capsule from the vaporizing unit, theuser couples the vaporizing unit to the reloading unit, beforeactivating the capsule-reloading mechanism, as described in furtherdetail hereinbelow. Subsequently, in order to smoke from the vaporizingunit, the user may, if desired, detach the vaporizing unit from thereloading unit. Typically, the vaporizing unit includes a mouthpiece 25.During a smoking session, the vaporizing unit typically vaporizes theactive ingredient of plant material that is disposed inside a capsule,by heating the capsule, while the capsule is disposed at thevaporization location. The user typically inhales the vaporized activeingredient via the mouthpiece.

Typically, smoking device 20 is configured to be portable and, duringuse, vaporizing unit 21 is configured to be held in a single hand of auser. The dimensions of the vaporizing unit are typically as follows:

-   -   A height H1 of reloading unit 22 is typically more than 5 cm        (e.g., more than 6 cm), and/or less than 15 cm (e.g., less than        12 cm), e.g., between 5 cm and 15 cm, or between 10 and 12 cm.    -   A height H2 of vaporizing unit 21, is typically more than 6 cm        (e.g., more than 8.3 cm), and/or less than 12 cm (e.g., less        than 10 cm), e.g., between 7 cm and 9 cm, or between 8 and 8.5        cm.    -   Typically, the total height HT of smoking device 20, including        the vaporizing unit inserted into the reloading unit is less        than 20 cm, e.g., less than 11 cm.    -   A width W of reloading unit 22 is typically more than 4 cm        (e.g., more than 6 cm), and/or less than 9 cm (e.g., less than        7), e.g., between 4 cm and 9 cm, or between 6 cm and 7 cm.    -   A depth D of reloading unit 22 is typically more than 2 cm        (e.g., more than 3 cm), and/or less than 6 cm (e.g., less than 4        cm), e.g., between 2 cm and 6 cm, or between 3 cm and 4 cm.    -   For applications in which vaporizing unit 21 has a circular        cross-section (as shown in FIG. 3 ), a diameter DI of the        vaporizing unit is typically more than 5 mm (e.g., more than 6        mm), and/or less than 35 mm (e.g., less than 20 mm), e.g.,        between 5 mm and 35 mm, or between 6 mm and 20 mm. For        applications in which the vaporizing unit has a non-circular        cross-section, the cross-sectional area of the vaporizing unit        is typically the equivalent of a circle having a diameter as        described in the previous sentence.

For some applications, a capsule-loading button 23 is disposed on theoutside of reloading unit 22. The capsule-loading button controlscapsule-loading mechanism 56 (FIGS. 8A-C). As described in furtherdetail hereinbelow, the capsule-loading mechanism is configured to (a)individually transfer unused capsules from a first receptacle 53 (FIG.9C) within the body of the reloading unit to a vaporization location 54(FIG. 6 ) within the body of vaporizing unit 21, at which the capsule isheated such as to vaporize the active ingredient, and (b) toindividually transfer used capsules from the vaporization locationwithin the vaporizing unit to a second receptacle 52 (FIG. 9C) withinthe body of the reloading unit. Alternatively or additionally,capsule-loading mechanism 56 (or any other capsule-loading mechanismdescribed herein) is controlled by an electric motor (not shown).

Reference is now made to FIGS. 4A-B, which are schematic illustrationsof respective views of a capsule 29, the capsule containing material 32,e.g., a plant material that includes an active ingredient, in accordancewith some applications of the present invention. As describedhereinabove, for some applications, the plant material is cannabis, andthe active ingredient is the constituent cannabinoids of cannabis (e.g.,tetrahydrocannabinol (THC) and/or cannabidiol (CBD)). Alternatively oradditionally, the plant material includes tobacco (and the activeingredient includes nicotine), and/or other plant or chemical substancesthat contain an active ingredient that becomes vaporized upon thesubstance being heated.

Typically, capsule 29 is generally similar to capsules described in WO16/147188, which is incorporated herein by reference. For someapplications, material 32 (which contains an active ingredient, andwhich is typically a plant material) is housed between plant materialcovering layers, which is typically include upper and lower meshes(e.g., metallic meshes) 30. For some applications, each of the mesheshas openings of more than 15 micron (e.g., more than 20 micron), and/orless than 80 micron (e.g., less than 50 micron), e.g., 15-60 micron, or20-50 micron. Typically, the meshes are coupled to a central portion 31of the capsule (e.g., a central disc, as shown), the central portiondefining a hole. For example, the meshes may be coupled to the centralportion via an adhesive, such as a high-temperature-resistant glue, ordouble-sided adhesive or ultrasonically welded to central portion orheat pressed onto central portion. Typically, the adhesive is configuredsuch that the adhesive does not emit fumes, even when the adhesive issubjected to a high temperature, such as a temperature of greater than200 degrees Celsius. Typically, the material is housed between themeshes and within the hole defined by the central portion of thecapsule.

Typically, plant material 32 is ground, such that (a) the material is insufficiently small pieces that the material fits within the capsule, anda large surface area of the material is exposed to air flow through thevaporizing unit (b) the pieces of the material are sufficiently largethat they do not pass through the meshes, and (c) the active ingredientwithin the material retains its potency. For some applications, thematerial is cryogenically ground and/or powderized.

For some applications, central portion 31 of capsule 29 is made of amaterial that has a high heat capacity and/or low heat conductivity sothat it reduces heat loss from the capsule to the surrounding area andreduces heating of the surrounding area during the vaporization process.For some applications, at least one of the wires of meshes 30 is hollow,and a phase-change material is disposed inside the hollow wire.Alternatively or additionally, a phase-change material is coupled to thecapsule is a different manner, e.g., by coating the capsule with thephase-change material. For some applications, the phase-change materialis configured to reduce heat loss from the capsule, by causing thecapsule to preferentially absorb heat relative to the areas surroundingthe capsule. Alternatively or additionally, the phase-change material isselected such as to maintain the capsule below the pyrolysis temperatureof the plant material, and to thereby prevent the plant material frombeing pyrolyzed. For example, the phase-change material may undergo aphase-change at a temperature that is between the vaporizationtemperature and the pyrolysis temperature of the plant material, suchthat the phase-change material absorbs heat as latent heat of fusion atthis temperature. For some applications, a phase-change material iscoupled to the capsule in order to facilitate the automaticidentification of the capsule type, by the control circuitry of thevaporizing unit, as described in further detail hereinbelow.

Reference is now made to FIG. 4C, which is a schematic illustration ofcapsule 29, the capsule including perforated sheets 60, in accordancewith some applications of the present invention. For some applications,plant material 32 is housed inside the central portion of the capsulebetween first and second perforated sheets. Typically, for applicationsas shown in FIG. 4C, upper and lower perforated sheets are used ascovering layers for covering the plant material, instead of the upperand lower meshes 30 as shown in FIG. 4B, for example. For someapplications, each of the perforated sheets defines one or moreperforations 62 that are configured to guide airflow through the plantmaterial along a given airflow path, during the vaporization process.For example, FIG. 4C shows airflow arrows 64, which illustrate anairflow path that is generated by perforations 62. Typically, theperforations are configured to guide airflow through the plant materialalong an airflow path that increases contact area between the flowingair and the plant material within the capsule). For some applications,the perforated sheets are configured to be heated in a similar manner tothat described herein with reference to meshes 30, mutatis mutandis. Forexample, the perforated sheets may be made of an electrical conductivematerial that is configured to be heated via resistive heating. Ingeneral, techniques that are described herein with reference to capsulethat include meshes 30 as the covering layers for covering the plantmaterial, may be performed with respect to capsules that includeperforated sheets 60 as the covering layers for covering the plantmaterial, mutatis mutandis.

Reference is now made to FIGS. 4D and 4E, which are schematicillustrations of meshes 30 or perforated sheets 60, in accordance withsome applications of the present invention. For some applications, theperforation pattern of the perforated sheets, or the pattern of holes inthe meshes, is uniform across the surface of each of the perforatedsheets, or each of the meshes, as shown in FIG. 4D, for example.Alternatively, the perforation pattern of the perforated sheets, or thepattern of holes in the meshes, is non-uniform across the surface ofeach of the perforated sheets, or each of the meshes, as shown in FIG.4E, for example. For some applications, the perforation pattern of theperforated sheets, or the pattern of holes in the meshes, is variedacross the surface of each of the perforated sheets, or each of themeshes, in order control the resistance and/or the resistivity patternof the sheet. For example, use of selective perforation may implementedin order to limit resistive heating to the contact area between theperforated sheet or the mesh and the plant material, and/or to focus theresistive heating upon that area. Alternatively or additionally,non-uniform perforation spacing may be used, for example, to control thecurrent density at different locations across the surface of theperforated sheets, or the meshes. An example of this is shown in FIG.4E, which shows slits 65 on mesh 30 or perforated sheet 60, the slitbeing configured to prevent electrical current from flowing across themesh or the sheet at regions at which the plant material is not housed.As described hereinabove, for some applications, perforations 62 aredisposed upon sheets 60 such as to guide airflow through the plantmaterial along a given airflow path, during the vaporization process.

Reference is now made to FIG. 4F, which is a schematic illustration ofcapsule 29, in accordance with some applications of the presentinvention. For some applications, capsule 29 is configured to beprovided to a user with plant material 32 within the capsule covered bynon-perforated sheets 66, the non-perforated sheets acting as thecovering layers for covering the plant material. For example, thecapsules may be provided to the user in this state, such that thenon-perforated sheets preserve the plant material within the capsule,and/or maintain the potency of the active ingredient within the plantmaterial. Typically, prior to the plant material being heated inside thevaporizer, sheets 66 are perforated, in order to allow airflow throughthe capsule. For some applications, the user perforates the sheets priorto placing the capsule inside the vaporizer. Alternatively, thevaporizer includes a perforating mechanism 67 that is configured toperforate sheets 66 prior to the plant material being heated inside thevaporizer. For example, as shown in FIG. 4F (which shows the perforatingmechanism in the absence of the other component of the vaporizer, forillustrative purposes), the perforating mechanism may include one ormore rollers 68 with pins 69 disposed thereon. For some applications,the perforation mechanism is configured to perforate sheets 66, suchthat the perforation pattern that is formed is uniform across thesurface of each of the sheets, for example, as shown in FIG. 4D.Alternatively, the perforation mechanism is configured to perforatesheets 66, such that the perforation pattern that is formed isnon-uniform across the surface of each of the sheets, for example, asshown in FIGS. 4C and 4E. For some applications, sheets 66 areconfigured to be heated in a similar manner to that described hereinwith reference to meshes 30, mutatis mutandis. For example, the sheetsmay be made of an electrical conductive material that is configured tobe heated via resistive heating. In general, techniques that aredescribed herein with reference to capsules that include meshes 30 asthe covering layers for covering the plant material, may be performedwith respect to capsules that include sheets 66 as the covering layersfor covering the plant material, mutatis mutandis.

For some applications, capsule 29 is configured to keep the plantmaterial fully encapsulated such that there is substantially no emissionof active ingredient prior to the vaporization of the active ingredientinside the vaporizer. For example, the capsule may be configured in thismanner by the use of non-perforated sheets 66, as described withreference to FIG. 4F.

Reference is now made to FIGS. 5-7 , which are schematic illustrationsof respective views of vaporizing unit 21, in accordance with someapplications of the present invention. For some applications, thevaporizing unit receives capsules by the vaporizing unit being coupledto reloading unit 22, and capsule-loading mechanism 56 being used toload capsules into the vaporizing unit. Alternatively or additionally,the vaporizing unit is used in the absence of the reloading unit, and,for example, a user may insert individual capsules into the vaporizingunit. For some such applications, after the user has smoked theindividual capsule, the individual capsule needs to be removed from thevaporizing unit before another capsule can be inserted. Alternatively,the vaporizing unit is configured such that a used capsule isautomatically pushed out of the vaporization location, by a new capsulebeg inserted into the vaporization location. Further alternatively, thevaporizing unit is configured to hold a plurality of used capsule, suchthat the used capsules only need to be removed from the vaporizing unitperiodically, and not after each capsule is smoked.

For some applications, the vaporizing unit of the smoking device isconfigured to be used with a plurality of different types of capsules.For example, respective types of capsules may contain differentquantities of plant material, plant material containing different amountof active ingredients, and/or different types of plant materials.Alternatively or additionally, respective types of capsules may haverespective characteristics, e.g., respective flavors, strengths,richnesses, active ingredients, etc. For some applications, thereloading unit is configured such that the user may select which capsuletype to place in the reloading unit, and the reloading unit may then beused to load the vaporizing unit with that type of capsule.Alternatively, a reloading unit may come preloaded with a given type ofcapsules. Further alternatively, as described hereinabove, thevaporizing unit may be configured such that the user can insert capsulesdirectly into the vaporizing unit. For such applications, the user isable to select which type of capsule he/she wishes to smoke at any giventime, and to insert that type of capsule into the vaporizing unit.

For some applications, control circuitry 34 of the vaporizing unit isconfigured to adjust a heating profile of the capsules to the capsuletype that is currently being heated. For some such applications, thecontrol circuitry implements an automatic capsule classificationprocedure in accordance with which the control circuitry automaticallyclassifies the capsule that is currently being heated as a given type ofcapsule (i.e., the control circuitry identifies the capsule type), anddesignates a capsule heating profile accordingly.

For some applications, color coded capsules are used for identificationof different capsules by the user and/or for automatic classification ofthe capsule by the control circuitry of the vaporizing unit, forexample, by use of a color sensor. For some applications, the thermalemissivity of the capsules is used for classification of differentcapsules by the control circuitry, for example, by coating one or moreof the metallic meshes of each of the capsules with coatings havingrespective thermal emissivity constants. For some applications, theidentification of the above-mentioned thermal emissivity constant of thecapsule is measured by the vaporizing unit, while the coating of thecapsule is at a known temperature. For example, the control circuitrymay measure the thermal emissivity of the capsule coating while thecapsule is in an unused state, and can therefore be assumed to beapproximately at ambient temperature. For some applications, a standardtemperature sensor is used to measure the temperature of the capsulecoating. For some applications, a temperature sensor as describedhereinbelow is used to measure the temperature of the capsule coating.

For some applications, the control circuitry is configured to performthe classification of the capsule type by phase-change materials havingrespective phase-change temperatures being used with each capsule type.Typically, the phase-change material is at least partially disposedwithin the capsules and is thermally coupled to one or more of themetallic meshes of the capsules. Further typically, the phase-changetemperature of the phase-change material is below the vaporizationtemperature of the active ingredient. During the heating of a capsule,the phase-change material reaches its phase-change temperature andaccumulates latent heat, while it is in the process of undergoing thephase change. In accordance with respective applications, within thetemperature range to which the capsule is heated, the phase-changematerial may be configured to undergo a phase change from solid toliquid, from liquid to gas, from gel to gas, and/or from solid to gas.Typically, while the phase-change material undergoes the phase change,the measured temperature of the phase-change material, and of thecapsule, remains constant. The constant temperature is typicallymaintained for a short duration of time, followed by a continuedincrease in the temperature of the capsule after the phase changetransition of the phase-change material has been completed. For someapplications, the control circuitry is configured to detect thetemperature at which the capsule's temperature remains constant for agiven period of time, during the heating of the capsule. Since thistemperature is indicative of the phase-change temperature, the controlcircuitry is configured to classify the capsule type in response todetecting this temperature. For example, different types of capsules canbe classified by using phase-change materials with pre-definedphase-change temperatures. Purely by way of example, phase-changematerials having phase-change temperature levels of approximately 60degrees Celsius, approximately 65 degrees Celsius, approximately 70degrees Celsius, approximately 75 degrees Celsius, and approximately 80degrees Celsius can be used to classify five different types ofcapsules. As described hereinabove, typically, in response to detectinga given capsule type, a capsule heating profile that is suited to thatcapsule type is applied.

For some applications, in cases in which it is desired to prohibit there-use of already vaporized capsules, the control circuitry isconfigured to detect a presence of a phase-change material within thecapsule. For some applications, the phase-change material is configuredto be vaporized, to dissipate, and/or to lose its phase changingproperties, in response to the capsule being used, due to itstemperature having been increased above its phase-change temperature.The control circuitry is configured to interpret the presence of thephase-change material within the capsule, and/or a characteristic of thephase-change material within the capsule, as indicating that the capsulewas not previously vaporized, and to allow the capsule to be heated,only in response thereto. For example, in cases in which re-use ofcapsules might cause an increased emission of harmful materials or mightcause pyrolysis of the dry, used active ingredient, the controlcircuitry may be configured as described.

For some applications, a phase-change material is mixed with the plantmaterial within the capsule. Alternatively or additionally, thephase-change material is shaped as a thin plate and is disposed withinthe capsule such that the phase-change material encapsulates the plantmaterial. In this manner, in addition to the thermal phase-changeproperties of the phase-change material described hereinabove, thephase-change material facilitates the preservation of and/or reduces thedegradation of the plant material, prior to the plant material beingheated.

For some applications, respective capsule types are provided with mesheshaving respective resistance levels. The control circuitry isconfigured, by measuring the resistance of the mesh, to identify thecapsule type that is currently being heated. As described hereinabove,typically, in response to classifying the capsule as a given capsuletype, a heating profile that is suited to that capsule type is applied.For some applications, constructing meshes having respective resistancesis performed by using materials with respective resistances, and/or bymodifying the mechanical properties of the meshes, such as length,width, cross section, and/ or any other property that might influencethe resistance. For some applications, a generally similar technique isperformed, but the capsules are identified via the electrical resistanceof a different portion of the capsules, for example, the main body ofthe capsules, a resistor embedded in the capsule, and/or resistance of amaterial within the capsule.

For some applications, capsules types are identified by use of othertypes of coding. For example, barcode, unique mechanical features (forexample: holes or grooves), switches, electro-optical switches, RFID, orany other applicable coding mechanism.

For some applications, vaporizing unit 21 includes a grill 26, which isconfigured to allow airflow into the body of the vaporizing unit, asdescribed in further detail hereinbelow. For some applications, acapsule loading and unloading opening 27 is configured to allow themanual and or mechanized loading and unloading of capsules into and outof the vaporization location within the vaporizing unit, as described infurther detail hereinbelow.

For some applications vaporizing unit 21 defines a groove 28, which isconfigured to facilitate insertion of the vaporizing unit into reloadingunit 22 in a given alignment. For example, the groove may be configuredto facilitate insertion of the vaporizing unit into the reloading unitsuch that capsule loading and unloading opening 27 is correctly alignedsuch as to receive capsule from receptacle 53 of the reloading unit, andto deposit capsules into receptacle 52 of the reloading unit.

For some applications, the inner surface of mouthpiece 25 (and/or otherportions of the vaporizer) includes a lipophobic or hydrophobic coatingthat is configured to prevent products of the vaporization of the activeingredient from sticking to the inner surface of the mouthpiece.Alternatively or additionally, a filter is used to filter at least apart of the vapors that pass through the mouthpiece. For someapplications, a filter that is similar to that of a traditionalcombustion cigarette is used, for example, in order to provide the userwith a look and feel that is similar to that of a cigarette during theuse of the vaporizing unit of the smoking device.

Typically, vaporizing unit 21 is inserted into reloading unit 22 for thepurpose of loading a new capsule into the vaporizing unit (e.g., to thevaporization location of the vaporizing unit), as described hereinabove.Alternatively or additionally, the reloading unit contains a powersupply 45 (FIGS. 8A-C and 9A-C), and an internal power supply 33 of thevaporizing unit is configured to become charged by the power supply ofthe reloading unit, by the vaporizing unit being coupled to reloadingunit. For some applications, power supply 45 of the reloading unit,and/or power supply 33 of the vaporizing unit is configured to receivepower from an external power source, such as mains electricity.Typically, the vaporizing unit is decoupled from the reloading unitprior to the user using the vaporizing unit to vaporize the activeingredient of the plant material, to thereby smoke from the vaporizingunit. During a smoking session, the vaporizing unit, which typically hasa shape that is generally similar to that of a cigarette, is held by theuser, and functions as an electronic cigarette.

Reference is again made to FIG. 6 , which is a schematic cross-sectionalillustration of vaporizing unit 21, in accordance with some applicationsof the present invention. Reference is also made to FIG. 7 , which is aschematic illustration of components vaporizing unit 21, in accordancewith some applications of the present invention. Typically, vaporizingunit 21 includes one or more heating elements, which are configured toheat the plant material within capsule 29 (such as to vaporize theactive ingredient within the plant material). For some applications,electrodes 36, 37, 38, and 39 are configured to act as heating elements,by heating the plant material within the capsule, by driving anelectrical current into capsule 29. As described hereinabove, for someapplications, capsule 29 includes one or more metallic meshes 30 (FIGS.4A-B). The electrodes heat the material inside the capsule by heatingthe one or more meshes via resistive heating, by driving a current intothe one or more meshes. Alternatively or additionally, the electrodesheat an internal heating element that is housed within the capsule, bydriving a current into the internal heating element. Typically, theelectric current that is driven is controlled, such that, for example,the heating of the capsules is not affected by variations in the degreeof contact between the electrodes and the meshes of the capsules.

For some applications, upper mesh of capsule 29 is electricallyconnected to the lower mesh, and at least two electrodes are used todrive an electrical current into capsule 29. For example, referring tothe view shown in FIG. 7 , electrodes 36 and 37 may be used, and theupper and lower meshes may be electrically connected to one another onthe far side of capsule 29. For some applications, the lower mesh and/orthe upper mesh is heated by the mesh being used to complete a circuitbetween a pair of electrodes. For example, the plant material containedwithin the capsule may heated by driving a current from first electrode36 to second electrode 39 via the lower mesh of capsule 29.Alternatively or additionally, the plant material contained within thecapsule may be heated by driving a current from third electrode 37 tofourth electrode 38 via the upper mesh of capsule 29. For someapplications, by heating the plant material in the aforementionedmanner, the plant material within the capsule is heated more uniformlythan if, for example, a monopolar electrode were to drive a current intoa location on the upper or lower mesh. For some applications, capsule 29includes an internal heating element (e.g., an internal mesh (notshown)), as an alternative or in addition to the upper and lower meshes.The internal heating element is configured to be heated in a similarmanner to that described with reference to the upper and lower meshes,and is configured to heat the capsule via conductive heating.

For some applications, springs 40 are coupled to at least some theelectrodes, e.g., electrodes 37 and 38 as shown in FIG. 7 . The springsare configured to push the electrodes towards the capsule 29, in orderto improve electrical coupling between the electrodes and the capsule.For some applications, the electrodes include a bladed tip that acts asthe electrical contact to the capsule. Typically, the tips of theelectrodes have a thickness of more than 0.05 mm (e.g., more than 0.1mm), and/or less than 0.4 mm (e.g., less than 0.3 mm), e.g., between0.05 mm and 0.4 mm, or between 0.1 mm and 0.3 mm.

For some applications, an electrode-movement mechanism (not shown) isconfigured to move at least a portion of the electrodes with respect toa mesh of capsule 29. For example, an electrode-movement mechanism asdescribed in WO 16/147188 to Raichman, which is incorporated herein byreference, may be used. For example, the electrode-movement mechanismmay move the electrodes closer to the mesh, and/or may move theelectrodes with respect to the mesh (e.g., by sliding the electrodesacross the surface of the mesh), while the electrodes are in contactwith the mesh. In this manner, the electrodes typically remove at leasta portion of a coating that has developed on the surface of the mesh,and/or penetrate the coating. For some applications, theelectrode-movement mechanism is configured to move the electrodes awayfrom the mesh, for example, in order to facilitate insertion of acapsule into the vaporization location or removal of a capsule from thevaporization location, in a manner that friction between the capsule andthe electrodes is reduced or eliminated.

Although vaporizing unit 21 has been described as using resistiveheating of electrode(s) 36, 37, 38, and/or 39 to heat capsule 29, forsome applications, alternative or additional heating elements andheating techniques are used to heat the capsule. For example, a laseremitter may act as a heating element by directing a laser beam at thecapsule, in order to heat the capsule. For some applications, a separateheating element that is housed inside the vaporizing unit is heated inproximity to the vaporization location, in order to provide conduction,convection, and/or radiation heating to the capsule.

During use of the vaporizing unit, the user typically inhales viamouthpiece 25. This causes air to flow through grill 26 (FIG. 5 ) to themouthpiece via the capsule, as indicated by the dashed airflow arrow inFIG. 6 . Typically, the capsule is configured to be placed at thevaporization location within the vaporizing unit, such that planesdefined by the upper and lower meshes are perpendicular to a directionof the air flow through the vaporizer at the vaporization location. Forsome applications, a sealing gasket 41 is used to prevent air fromoutside the vaporizing unit from flowing into mouthpiece 25 withoutpassing through capsule 29.

Typically, a power supply 33 (e.g., a battery) and control circuitry 34are housed inside the body of vaporizing unit 21. Typically, the powersupply and/or the control circuitry are coupled to the body of thevaporizing unit by a coupling element, such as an adhesive, a screw, aclip, and/or a pin. For some applications, the control circuitry isconfigured to drive a current into the capsule via electrodes 36, 37,38, and/or 39, using power supplied by the power supply.

Typically, the control circuitry comprises electronic components, suchas resistors, transistors, capacitors, inductors and diodes. For someapplications, the control circuitry includes a computer processor, whichtypically acts as a special purpose vaporization-controlling computerprocessor. Typically, the operations described herein that are performedby such a computer processor transform the physical state of a memory,which is a real physical article, to have a different magnetic polarity,electrical charge, or the like depending on the technology of the memorythat is used.

For some applications, vaporizing unit 21 includes a temperature sensor35 that is configured to measure an indication of the temperature of thematerial that is being heated, e.g., by measuring the temperature of thecapsule that is being heated. For example, the temperature sensor may bean optical temperature sensor, such as an infrared temperature sensor,that is configured to measure the temperature of the capsule withoutcontacting the capsule. FIGS. 6-7 shows sensor 35 aligned to receivebeams of optical light from capsule 29, the capsule having been heated.Sensor 35 is configured to measure the temperature of capsule 29, basedupon the received light. In this manner, the optical temperature sensormeasures the temperature of the capsule, without affecting thetemperature of the capsule by drawing heat from the capsule. For someapplications, the temperature sensor is covered with a lipophobic orhydrophobic coating that protects the temperature sensor from productsof the vaporization being deposited upon the temperature sensor. Thetemperature sensor typically has a “near zero” response time, such thatthe control circuitry is able to measure changes in temperature due tochanges in airflow, and respond to such changes in the manner describedhereinbelow, effectively immediately with respect to the perception ofthe user. For example, the temperature sensor may be configured todetect changes in temperature within 0.01 seconds, e.g., within 1millisecond, of such changes. For some applications, by virtue of havingsuch a temperature sensor, the control circuitry is configured torespond to airflow-induced changes in temperature within 0.01 seconds,e.g., within 1 millisecond, of such changes.

For some applications, vaporizing unit 21 includes a fan 48 (FIG. 6 )that is configured to vent out vapors during the heating process, byventilating a space between temperature sensor 35 and the capsule.Typically, during heating of the plant material, vapors are emitted. Insome cases, in the absence of fan 48, the vapors may mask the capsuleand/or the plant material from temperature sensor 35. In turn, this maycause errors in the temperature that is measured by the temperaturesensor (and particularly if sensor 35 is an infrared temperaturesensor). For example, the sensor may measure the temperature of theplant material as being lower than it actually is, which could lead tothe plant material being overheated, causing damage, pyrolysis, and/oror ignition of the plant material. Therefore, for some applications, fan48 vents vapors from the vaporizing unit during at least a portion ofthe heating process, by driving air into and/or out of the vaporizingunit. Alternatively or additionally, unwanted vapor accumulation withinthe device is reduced by designing internal passages of the device withdimensions that are such to allow air flow between the temperaturesensor and the plant material that is sufficient to prevent vaporaccumulation.

For some applications, a different temperature sensor is used. Forexample, the control circuitry may detect the temperature of the capsuleby detecting changes in the resistance of components of the capsule(e.g., mesh 30 of the capsule) using electrodes 36, 37, 38, and/or 39.

For some applications, smoking device 20 includes a port (not shown) viawhich the smoking device is connected to an external source of powerand/or data input. For example, power supply 45 of reloading unit 22 maybe configured to be recharged by connecting the smoking device to anexternal power supply (e.g., mains electricity) via the above-mentionedport. Alternatively or additionally, control circuitry 34 may receivedata, e.g., programming instructions, via above mentioned port.

For some applications, a user may input instructions into the controlcircuitry that control the amount of heat that is applied for a givenrate of airflow through the capsule. For example, the user may input theinstructions via a user interface 10 (such as a touchscreen display, orbuttons), shown in FIG. 3 , that is coupled to the control circuitry.Alternatively or additionally, the user may input the instructions via acomputer, a tablet device, a phone, and/or a differenttelecommunications device that communicates with the control circuitryvia a wired or a wireless communications protocol. For example, the usermay indicate a type of smoking that he/she desires (e.g., intense,slow-burn, etc.), and the control circuitry may control the amount ofheat that is applied for a given rate of airflow through the capsule, inresponse thereto. For some applications, the control circuitry isconfigured to automatically determine a desired smoking profile, basedupon the rate of airflow through the vaporizing unit (e.g., through thecapsule), as described in further detail hereinbelow. By controlling theamount of heat that is applied for a given rate of airflow through thecapsule, the amount of the active ingredient that is vaporized per unitairflow rate through the vaporizer may be controlled. For someapplications, vaporizing unit 21 includes an airflow sensor, (notshown). For some applications, the control circuitry is configured toautomatically determine the rate of airflow through the vaporizer, bydetecting the temperature of the capsule, as described in further detailhereinbelow.

For some applications (not shown), vaporizing unit 21 is shaped todefine a supplementary airflow channel, which provides airflow out ofmouthpiece 25, but not via the capsule that is being vaporized (notshown). In this manner, in response to a large inhalation by the user,the vaporizer is able to provide air to the user, without increasing thedosage of the active ingredient that is provided to the user.

For some applications, control circuitry 34 of the vaporizing unit orcontrol circuitry of the reloading unit (not shown) includes one or moreindicators for generating alerts to the user. For example, the controlcircuitry may illuminate an indicator light, may cause the vaporizingunit to vibrate, and/or may emit an audio signal (e.g., a beep).Alternatively, the vaporizing unit may include user interface 10, whichmay include a display (e.g., an LED or LCD display), and the controlcircuitry may generate an alert on the display. For some applications,the control circuitry is configured to generate an alert to the user inresponse to sensing that, during inhalation from the vaporizer by theuser, the temperature of the plant material is less than a giventhreshold temperature. Alternatively or additionally, the controlcircuitry is configured to generate an indication to the user inresponse to sensing that the temperature of the plant material isgreater than a given threshold temperature (e.g., a temperature of morethan between 300 degrees Celsius and 350 degrees Celsius), which maycause the material to become pyrolyzed or ignite. For some applications,the threshold is measured with respect to an expected targettemperature. For example, an alert may be generated in response tosensing a temperature that is 50 degrees Celsius less than an expectedtarget temperature. Further alternatively or additionally, the controlcircuitry is configured to generate an indication to the user that acapsule is faulty, is incorrectly placed, and/or is missing, in responseto measuring a temperature that is less than a given threshold, duringthe heating process.

Reference is now made to FIGS. 8A-C, which are schematic illustrationsof smoking device 20, showing vaporizing unit 21 placed in a portion ofreloading unit 22, at respective stages of the operation ofcapsule-loading mechanism 56, in accordance with some applications ofthe present invention. Reference is also made to FIGS. 9A-C, which areschematic cross-sectional views of smoking device 20, showing vaporizingunit 21 placed in a portion of reloading unit 22, at respective stagesof the operation of capsule-loading mechanism 56, in accordance withsome applications of the present invention.

Typically, reloading unit 22 of smoking device 20 includes first andsecond receptacles 53 and 52 (shown in FIG. 9C), which are configured tohouse capsules 29. Unused capsules are typically housed in a stackedconfiguration (i.e., such that when the smoking device is in an uprightorientation, the capsules are arranged one above the other) inside firstreceptacle 53, and used capsules are housed in a stacked configurationinside second receptacle 52. Typically, a spring 46 and a pushingelement 47 are coupled to a bottom of first receptacle 53. The springand pushing element are configured to maintain the stacked configurationof the capsules inside the first receptacle by pushing the capsulestoward the top of the first receptacle within the reloading unit. Forsome applications, by storing the capsules in stacked configurations,dimensions of the width and depth of smoking device 20 may be such thatthe smoking device can be comfortably held by a user (e.g., within asingle hand of the user) or carried in the user's pocket.

For some applications, capsules 29 have circular cross-sections, andreceptacles 52 and 53 define cylindrical tubes that house the capsules.Alternatively, capsules 29 may have a different shape, and receptacles52 and 53 may define hollow spaces that are shaped so as to conform withthe shapes of the capsules. For example, as shown in FIG. 4A, thecapsules may have a racetrack-shaped cross section.

Typically, the capsule-loading mechanism 56 is configured to (a)individually transfer unused capsules from first receptacle 53 insidereloading unit 22 to vaporization location 54 (FIG. 6 ) insidevaporizing unit 21, at which location the capsule is heated such as tovaporize the active ingredient of the plant material, and (b) toindividually transfer used capsules from the vaporization location tosecond receptacle 52 located inside reloading unit 22.

For some applications, vaporizing unit 21 is configured to becomecoupled to reloading unit 22, such that the top of receptacle 53 and thetop of receptacle 52 inside reloading unit 22, and vaporization location54 (FIG. 6 ) inside vaporizing unit 21, are linearly aligned with eachother (for example, across the width of the smoking device, as shown inFIGS. 9A-C). For some such applications, capsule-loading mechanism 56 isa linear capsule-loading mechanism, configured to move each of thecapsules by moving linearly. The capsule-loading mechanism is configuredto push unused capsules from receptacle 53 to vaporization location 54(FIG. 6 ) at which location the capsule is heated, and from thevaporization location to second receptacle 52 inside reloading unit 22.

As described hereinabove, for some applications, receptacle 53 ofreloading unit 22 houses pushing element 47 and spring 46, which iscoupled to the pushing element. For some applications, an upper capsulestopper 50 is used in the upper part of receptacle 53. The upper capsulestopper 50 is configured to limit the upmost position of the uppercapsule of the stack within receptacle 53, such that the upper capsuleis prevented from blocking or disturbing the movement of capsule-loadingmechanism 56.

For some applications, a capsule-loading button 23 is used in order tolinearly move capsule-loading mechanism 56. Alternatively oradditionally, capsule-loading mechanism 56 is configured to be moved byan electrical motor (not shown) that is controlled by control circuitryinside reloading unit 22.

Reference is now made to FIGS. 8A and 9A, which schematically illustratecapsule-loading mechanism 56 in its initial rest stage, in accordancewith some applications of the present invention. At this stage, springs42 apply force to a capsule-engagement plate 44 of capsule-loadingmechanism 56, causing plate 44 to be located at the beginning of itslinear travel path (at the right-most position, as shown in FIGS. 8A and9A). At this position, the capsule-engagement plate is configured toengage the upper-most capsule of the stack of capsules in receptacle 53,ready for the beginning of a new capsule loading cycle.

Reference is now made to FIGS. 8B and 9B, which schematically illustratecapsule-loading mechanism 56 in a second stage of its operation, duringthe loading of an unused capsule from the top of receptacle 53 insidereloading unit 22, into the vaporization location 54 (FIG. 6 ) insidevaporizing unit 21. For some applications, in order to reload a newunused capsule into the vaporizing unit 21, button 23 is presseddownwards by the user. For some such applications, button 23 is coupledto a pinion circular gear 43, and the button is configured such that,when button 23 is pressed by the user, its linear downwards motion turnsthe pinion circular gear 43. For some such applications, a rack lineargear 49 is disposed on capsule-engagement plate 44, and is configured toengage pinion circular gear 43, such that circular movement of pinioncircular gear 43 is transformed into a linear motion ofcapsule-engagement plate 44 from its initial position towards thevaporization location 54 (FIG. 6 ) inside vaporizing unit 21. Theabove-mentioned movement of capsule-engagement plate 44 pushes theupper-most unused capsule within receptacle 53 into the vaporizationlocation 54 (FIG. 6 ) inside vaporizing unit 21. In some cases, a usedcapsule 51 from a previous vaporization is positioned in thevaporization location prior to the reloading of a new unused capsule.Typically, the capsule-loading mechanism is configured such thatinsertion of the unused capsule into the vaporization location by thecapsule-loading mechanism, pushes used capsule 51 out of thevaporization location toward receptacle 52.

For some applications, as shown, pinion circular gear 43 includes acombination of two circular gears with different radii, such as tocreate a transformation ratio that reduces the downwards distancethrough which button 23 must be moved, in order to movecapsule-engagement plate 44 from its initial position to its endposition, relative to if a single circular gear were to be used.

Reference is now made to FIGS. 8C and 9C, which schematically illustratecapsule-loading mechanism 56 in a final stage of its operation. At thisstage, as shown, button 23 is typically fully pressed,capsule-engagement plate 44 has fully placed a new, unused capsule intovaporization location 54 (FIG. 6 ), ready for heating. Previously usedcapsule 51 is fully emitted out of vaporizing unit 21 into receptacle 52and springs 42 are fully compressed. For some applications, as button 23is released, springs 42 push capsule-engagement plate 44 back to itsinitial rest point (as shown in FIGS. 8A and 9A). Button 23, which iscoupled to capsule-engagement plate 44 by the abovementioned rack andpinion gears, is typically automatically pushed back its initialposition by the rack and pinion gears, ready for a new capsule loadingcycle.

For some applications, reloading unit 22 includes an indicator 58 (FIG.1 ) that indicates to the user how many unused capsules are housedwithin the reloading unit 22. For some applications, rather than thereloading unit being configured to be refilled, some of the componentsof smoking device 20 are recyclable and are transferrable to an unusedreloading unit. For example, a single vaporizing unit 21 could be usedwith a plurality of reloading units, each of which is configured forsingle use. For some applications (e.g., applications in which thedevice is used with cannabis that is administered for medicinalpurposes), the size of the capsules and/or the amount of plant materialin each capsule that is to be provided to a given user may be determinedby a healthcare professional. In addition, as described hereinabove, thesmoking device is typically programmable, such that, for example, only acertain dosage of the active ingredient may be released per use, perpuff, or within a given time period. In this manner, if the plantmaterial that is used inside the smoking device is a regulated substance(e.g., cannabis), control over the use of the substance may bemaintained. For some applications, the smoking device, the reloadingunit, the vaporizing unit, and/or the capsules include identifying marksor tags (e.g., an RFID or a barcode), such as to facilitate regulationand control of the use of the smoking device and the capsule.

For some applications, reloading unit 22 does not include receptacle 52,and previously used capsules are ejected from the vaporization locationout of the vaporizing unit without being stored inside the reloadingunit. For some applications, button 23 and circular gear 43 are not usedand an electrical motor is coupled to capsule-engagement plate 44, suchas to generate the linear movement for capsule loading. For someapplications, a different type of capsule-loading mechanism is used,mutatis mutandis. For example, a capsule-loading mechanism may be usedthat is generally similar to any one of the capsule-transfer mechanismsas described in WO 16/147188 to Raichman, which is incorporated hereinby reference.

Reference is now made to FIG. 10 , which is a graph with respectivecurves illustrating respective techniques for heating plant materialusing a vaporizer, such as vaporizing unit 21, in accordance with someapplications of the present invention. The x-axis of the graph indicatesnormalized airflow rate (measured as a percentage), and the y-axisindicates the temperature (measured in degrees Celsius) to which acapsule that contains a plant material is heated at a given airflowrate. Typically, the airflow rate percentage is measured with referenceto a maximal airflow rate that a typical user would generate by inhalingfrom the vaporizer. By way of example, the airflow rate may be measuredas a percentage of an airflow rate of between 0.8 and 1.2 liters perminute.

As described hereinabove, for some applications, vaporizing unit 21 isused to vaporize active ingredients within tobacco. Tobacco typicallyhas a vaporization temperature of 150 to 230 degrees Celsius, and beginsto become pyrolyzed at 250 degrees Celsius. Therefore, it is typicallydesirable to heat the tobacco to a temperature of between 150 degreesCelsius and 230 degrees Celsius. Further typically, it is desirable notto heat the tobacco to a temperature that is greater than 230 degreesCelsius, in order to prevent pyrolysis of the tobacco. Typically, whenthe vaporizer is used with materials other than tobacco, similarconsiderations are applicable, although the desired temperature to whichthe material should be heated will vary depending on the characteristicsof the material that is being used with the vaporizing unit.

Mouthfullness is an attribute that smokers refer to that relates to thetexture and feel of tobacco smoke in the mouth. While smoking acombustible cigarette, the combustion speed, and therefore the amountand density of the generated smoke are directly related to airflow ratethrough the cigarette. By controlling of inhalation rate, cigarettesmokers can adjust the mouthfullness according to their personal tasteand preferences.

For some applications, the feeling of mouthfullness is at leastpartially replicated when using a vaporizer (for example, vaporizingunit 21) by heating the plant material within the capsule as a functionof airflow rate through the vaporizer (for example, air flow throughcapsule 29 shown in FIG. 6 ), which is indicative of the inhalation rateof the user. Typically, this enables the user to have control over atleast some of the properties of the generated active ingredient vapors.

For some materials (for example, tobacco and cannabis), increasing thetemperature of the capsule causes an increase in the vaporization rateof the active ingredient, with more vapors being emitted as temperatureis set higher. For some materials, increase of vaporization temperatureinfluences the taste of the generated vapors. Some materials (forexample, various types of tobacco), when heated to the lower end oftheir vaporization temperature range, emit light tasted vapors, and whenheated to higher temperatures within their vaporization temperaturerange, generate vapors having a different taste, e.g., more heavy, rich,woody, or smoked.

For some applications, the plant material is initially heated to atemperature point at the lower end of the vaporization temperature rangeof the plant material. The temperature is then increased within thevaporization temperature range according to a function of the detectedinhalation air flow through the vaporizer (e.g., through the capsule ofthe vaporizer), with the maximum temperature to which the capsule isheated typically being limited, in order not to exceed plant material'spyrolysis temperature. For some applications, the plant material isheated to a lower temperature when lower airflow rate is detected and toa higher temperature when a high airflow rate is detected. For example,the temperature to which the capsule is heated may be increased indirect proportion to increases in the normalized airflow through thevaporizer, as denoted by the solid curve in FIG. 10 . Also, as shown bythe solid curve of FIG. 10 , for some applications, when the capsule isheated to a pre-defined maximal temperature (of approximately 230degrees Celsius, as shown in FIG. 10 ), additional heating is withheld,e.g., to avoid reaching the pyrolysis temperature of the plant material.

For some applications, the capsule containing the plant material isinitially heated to a temperature point below the lower end of thevaporization temperature range of the plant material. When little to noair flows through the capsule, the sub-vaporization temperature of theplant material will prevent the vaporization of the active ingredient.Upon detection of an increase in airflow rate, the control circuitryrapidly increases the temperature of the plant material to a pointwithin the vaporization temperature range of the plant material. Ondetection of an additional increase in inhalation air flow, the capsuletemperature is adjusted according to the detected airflow rate.

For some applications, in response to receiving a first input at thevaporizer (e.g., in response to the user pressing an ON switch on thevaporizer), the control circuitry of the vaporizer initiates apre-heating step. Typically, the pre-heating step is a rapid heatingstep (e.g., a heating step in which the capsule that contains the plantmaterial is heated at a rate of more than 50 degrees Celsius per second,or more than 100 degrees Celsius per second). Further typically, thecontrol circuitry of the vaporizer is configured to terminate the firstheating step, by withholding causing further temperature increase of thecapsule, in response to detecting that the temperature of the capsule(which is indicative of the temperature of the plant material) hasreached a pre-defined first temperature. Typically, the firsttemperature is more than 80 percent and less than 120 percent of the lowend of the plant material vaporization range, e.g., more than 90 percentand less than 110 percent, or more than 85 percent and less than 95percent, or more than 105 percent and less than 115 percent of the lowend of the used active ingredient vaporization temperature range. Forexample, when the vaporizer is used to vaporize tobacco, the controlcircuitry of the vaporizer may be configured to withhold causing furthertemperature increase of the capsule, in response to detecting that thetemperature of the capsule has reached a pre-determined temperature thatis less than 170 degrees Celsius (e.g., less than 150 degrees Celsius),e.g., a temperature that is between 120 and 130 degrees Celsius, orbetween 130 and 140 degrees Celsius. For some applications, in responseto the detection of airflow through the plant material, the plantmaterial's temperature is increased at a rate of between 0.5 to 10degrees Celsius per percent of airflow rate increase, e.g., atemperature increase of 0.5 to 2 degrees Celsius, 2 to 8 degreesCelsius, or 5 to 10 degrees Celsius per percent of airflow rateincrease.

For some applications, to enable the performing of airflow rate relatedheating of the plant material, the vaporizer (for example vaporizingunit 21) is configured to enable fast heating of the plant material inorder to rapidly adjust the temperature of the plant material to changesin the airflow rate during the inhalation, for example, to enable atemperature increase of more than 20 degrees Celsius per second (e.g.,more than 50 or more than 100 degrees Celsius per second). For someapplications, the target temperature to which the plant material isheated is dynamically updated in order to adjust the vaporizationtemperature and vaporization rate according to the desired smokingprofile of the user. For some applications, the target temperature towhich the plant material is heated is dynamically updated in acontinuous manner. For some applications, the capsule is heated to atarget a temperature that is derived as a continuous function of thedetected airflow rate. For example, the continuous function may be apolynomial function, a monotonically increasing function, amonotonically decreasing function. Alternatively, the target temperatureto which the plant material is heated is dynamically updated on apuff-by-puff basis, i.e., with each inhalation of the user, the controlcircuity calculates a target temperature to which the capsule should beheated for that inhalation. For some applications, the control circuitydetects that the user is starting to inhale from the vaporizing unit byreceiving an input via a user interface located on the reloading unit orthe vaporizing unit. Alternatively or additionally, the control circuitydetects that the user is starting to inhale from the vaporizing unit bydetecting the temperature of the capsule, and/or by detecting anindication of an amount of energy required to maintain the temperatureof the capsule constant.

For some applications, the control circuitry of the vaporizer calculatesthe airflow rate through the capsule by measuring the electrical powerneeded to maintain the capsule that houses the plant material at adesired temperature. In order to enable the use of this technique forairflow measurement, the plant material is typically initially heated toa temperature that is above the ambient air temperature, for exampleto50 degrees Celsius or more (as shown by the dashed curve in FIG. 10 ),or to 120 degrees Celsius or more (as shown by the solid curve in FIG.10 ). Typically, once the capsule has been heated above the ambienttemperature and ambient air is then made to flow through the capsule bythe user inhaling, the electrical power needed to maintain the capsuleat a given temperature is related to airflow rate and the temperaturegradient between the capsule and the flowing ambient air. Therefore, thecontrol circuity is configured to determine the airflow rate based uponthe current temperature of the capsule, and the electrical power neededto maintain the capsule at the temperature. For example, the controlcircuitry may measure the electrical power needed to maintain thecapsule at the temperature by detecting variations in the duty cyclethat is used to heat the capsule. For some applications, the temperatureof the capsule is not held constant, and the control circuitrydetermines the airflow rate through the capsule at least partially basedupon measured changes in temperature of the capsule resulting fromchanges in airflow rate through the capsule. For example, the controlcircuitry may continue to heat the capsule at a fixed power, and measurethe changes in temperature of the capsule. Typically, such changes intemperature are indicative of the airflow rate through the capsule.Alternatively, the control circuitry may stop heating the capsule whenthe capsule is at a given temperature, and measure changes in thetemperature of the capsule. Typically, such changes in temperature arecorrelated with the rate of airflow through the capsule, since themeasured change in temperature is indicative of induced heat transferfrom the heated capsule to the ambient air, by convection, which, inturn, is indicative of the rate of airflow through the capsule. For someapplications, the control circuitry is configured to measure ambienttemperature and/or humidity in order to calculate airflow rate inaccordance with the technique described herein. Typically, in order tocalculate the airflow rate, the control circuitry accounts for thedifference between the temperature of the capsule (and therefore theplant material), and the ambient temperature.

For some applications, functions are used to determine the targettemperature to which the capsule is heated, based upon the detectedairflow rate indication, according to the material in use, the desireduser experience or any other relevant factor. For some applications, inaddition to airflow rate measurement, inputs are received by the controlcircuitry from additional sources, in order to determine the targettemperature to which to heat the capsule. For example, as describedhereinabove, the control circuitry may be configured to classify acapsule as a given capsule type, and to control the heating of thecapsule based upon a heating profile that is specifically suited to thatcapsule type. For example, different types of capsules may havedifferent airflow-rate-to-target-capsule-temperature profiles applied tothem. For example, one type of capsule may follow a profile as indicatedby the solid curve of FIG. 10 , another capsule type may follow aprofile as indicated by the dashed curve of FIG. 10 , and yet anothercapsule type may follow a profile as indicated by the dotted curve ofFIG. 10 . For some applications, a user inputs a desired heatingprofile, for example, using user interface 10 (shown in FIG. 3 ).

For some applications, by performing the heating of the capsule in theairflow related process described hereinabove, one or more of thefollowing results are achieved:

1) When smoking a traditional combustion cigarette, an increase in theuser's inhalation rate increases generated smoke due to intensificationof cigarette flame. In addition, the temperature of the inhaled smoke istypically greater. Therefore, for some applications, the targettemperature to which the capsule is heated is correlated to airflow rate(which is indicative of user inhalation rate), in order to simulate theburning of a traditional cigarette as described above. As describedhereinabove, typically the capsule is not heated above a predefinedmaximal temperature limit (which is typically less than 90 percent ofthe pyrolyzation temperature of the plant material). Typically, thepredefined maximal temperature limit is set such that the plant materialis not heated to a temperature that is greater than the pyrolysistemperature of the plant material, and/or such that the plant materialis not heated to a temperature that will produce smoke and/or a badtaste. By dynamically adjusting the target vaporization temperature asdescribed hereinabove, the taste and “mouthfullness” of the generatedvapors are adjusted according to user's individual taste andpreferences. For example, users that prefer a long and slow inhalationwill benefit from receiving a constant slow supply of the vaporizedactive ingredient, due to the relatively lower vaporization temperaturethat will be generated by the lower airflow rate of the slow inhalation.On the other end, users that prefer a faster and more intense release ofthe active ingredient will enjoy the higher rate of active ingredientvaporization rate that will result from the higher vaporizationtemperature to which the plant material is heated, due to their elevatedinhalation airflow rate.

2) Dynamically adjusting the target temperature to which the plantmaterial is heated as described hereinabove, may provide higherefficiency in the consumption rate of the plant material. For example,users that prefer taking several relatively short puffs will not sufferfrom loss of plant material between the short puffs, since the controlcircuitry will lower the target temperature to which the capsule isheated between the puffs.

3) Dynamically adjusting the target temperature to which the capsule isheated as described hereinabove, may reduce loss of active ingredientprior to the beginning of user inhalation. The lack of airflow prior tothe user's inhalation will result in the target temperature to which thecapsule is heated being relatively low, such as to reduce vaporizationof active ingredient prior to user inhalation.

4) In some cases, a delivery of a constant dose of the active ingredientis desired on every puff. For a given arrangement of plant material, themass of the active ingredient that is vaporized is a function of, atleast, the temperature of the material and of the airflow rate throughthe material. For some applications, an airflow-related heating processis used as described hereinabove, and the control circuitry responds tothe measured airflow indication, such as to deliver a constant dose ofthe active ingredient for each puff of the vaporizing unit. For example,a function may be used in accordance with which the vaporizationtemperature is reduced in response to the airflow increasing.

5) For some applications, the control circuitry additionally accountsfor the amount of active ingredient that has already been vaporized fromthe portion of the plant material that is currently being heated (whichmay, for example, be a portion of the plant material that is disposedinside a capsule). For example, in some cases, based on the rates ofairflow and temperatures that have already been applied to the capsulethat is currently being heated, the control circuitry may determine anamount of the active ingredient that has already been vaporized. Forsome applications, the control circuitry determines the targettemperature to which to heat the capsule, in response to the amount ofactive ingredient that has already been vaporized. For someapplications, the control circuitry determines the target temperature towhich to heat the capsule, in response to (a) the amount of activeingredient that has already been vaporized, as well as (b) the currentmeasured airflow through the vaporizing unit (e.g., through the plantmaterial that is being heated within the vaporizing unit). For example,for a given airflow rate, the control circuitry may heat the capsule toa greater temperature, the greater the amount of the active ingredientthat has already been vaporized. This may be because, once a givenamount of the active ingredient has already been vaporized from theplant material, the plant material may need to be heated to a greatertemperature in order for the remaining active ingredient to bevaporized. For some applications, in response to determining that agiven amount of the active ingredient has already been released from theplant material, the control circuitry may be configured to reduce thetemperature of the plant material to a sub-vaporization temperature,such as to withhold additional vaporization of active ingredient.

For some applications, in response to the detected rate of air flowthrough the vaporizer, the control circuitry calculates the dosage ofthe active substance that has been provided to the user. For someapplications (e.g., when the vaporizer is used with cannabis formedicinal purposes), a healthcare professional inputs instructions intothe control circuitry that control the amount of airflow through thevaporizer that is permitted during each use of the vaporizer, and/or theamount of airflow through the vaporizer that is permitted within a giventime period (e.g., per hour, or per day, or per puff). Alternatively oradditionally, the control circuitry may control the heating rate perunit airflow rate, as described hereinabove. For example, in order todeliver a constant dose of active ingredient to the user, the controlcircuitry may be configured to decrease the temperature to which thecapsule is heated, in response to detecting an increase in the airflow,as indicated by the dotted curve in FIG. 10 . For some applications, thedecrease in temperature is configured to keep a constant activeingredient vaporization rate. For some applications, the controlcircuitry combines the aforementioned temperature control functionalitywith setting a time limit for the heating that is applied in response toeach puff of the vaporizer. In this manner, a constant dose is deliveredto the user on each puff, regardless of the airflow rate of the puff.

For some applications, in response to detecting that no inhalation hasoccurred over a given time period (e.g., a time period of between 0.5seconds and 3 seconds), the temperature of the capsule is reduced tobelow the vaporization temperature of the plant material. For example,during use of the vaporizer, the user may stop inhaling for a given timeperiod, due to coughing, and/or due to irritation caused by the activeingredient. By reducing the temperature to below the vaporizationtemperature, wastage of the plant ingredient during this period isreduced.

Referring again to FIG. 10 , for some applications a heating profile isapplied as indicated by the solid curve. For example, betweenapproximately 0 airflow rate percentage units and 70 airflow ratepercentage units the control circuitry causes the temperature of thecapsule to be modified along a temperature range of 120 to 230 degreesCelsius. This is performed by detecting the current inhalation airflowrate and adjusting the temperature according to the curve. Fromapproximately 70 airflow rate percentage units to 100 airflow ratepercentage units, the capsule maintains a maximal temperature of 230degrees Celsius. More generally between 0 airflow and a given airflowrate, the control circuitry may control the temperature of the capsulein proportion to the airflow rate, up to a maximum temperature. For someapplications, the maximal temperature is between 200 degrees Celsius and230 degrees Celsius. Beyond the given airflow rate, the controlcircuitry typically maintains the capsule at the maximum temperatureeven if the airflow rate increases.

For some applications, a heating profile is applied as indicated bydashed curve in FIG. 10 . For example, between 0 airflow rate percentageunits and a first given airflow rate (e.g., 20 airflow rate percentageunits, as shown in FIG. 10 ) the control circuitry may increase thetemperature of the capsule in response to the increases in airflow rate,at a first rate. Between the first given airflow rate and a second givenairflow rate (e.g., 70 airflow rate percentage units, as shown in FIG.10 ), the control circuitry may increase the temperature of the capsulein response to the increases in airflow rate, at a second rate. For someapplications, the second rate is lower than the first rate, i.e., at thesecond rate, the temperature increase in response to a given rise inairflow rate is less than the temperature increase that is applied inresponse to the same airflow rate rise, at the first rate. For someapplications, beyond the second given airflow rate, the capsule ismaintained at a given maximum temperature (e.g., a temperature of 230degrees Celsius), even if the airflow rate increases.

As described hereinabove, for some applications, a heating profile isapplied as indicated by dotted curve in FIG. 10 . For such applications,in response to an increase in the airflow rate, the temperature to whichthe capsule is heated by the control circuitry is reduced.

Reference is now made to FIG. 11 , which is a graph illustrating theheating curves of capsules that include phase-change materials, inaccordance with some applications of the present invention. As describedhereinabove, for some applications, in order to enable theidentification of the capsule type, use is made of the vaporizing unit'sbuilt-in temperature sensor, in combination with phase-change materialsthat are configured to have respective phase-change temperatures beingincluded within respective capsule types.

The solid curve in FIG. 11 represents the heating curve of a capsulethat includes or is thermally coupled to a phase-change material with aphase-change temperature of 85 degrees Celsius. As shown, when applyingheat at a constant predefined power to the capsule, the temperature ofthe capsule rises in proportion with the heating power that is applied.When reaching the phase-change material's phase-change temperature of 85degrees Celsius (at 150 milliseconds), a large amount of energy in theform of latent heat is accumulated by the phase-change material at arelatively constant temperature, resulting in a detectable pause in thetemperature increase of the capsule. For some applications, by detectingthe temperature level at which the temporary pause in the temperatureincrease occurs, the control circuitry classifies the capsule as being agiven type of capsule and adjusts the heating profile and/or otherrelevant functions accordingly. At a certain point in time, when thephase-change material has undergone its phase change, the temperature ofthe capsule continues to rise due to the applied heat energy, as seen onthe solid curve of FIG. 11 after 200 milliseconds.

The dotted curve in FIG. 11 represents the heating curve of a capsulethat includes or is thermally coupled to a phase-change material with aphase-change transition temperature of 105 degrees Celsius. The heatingcurve of the capsule is generally similar to that described withreference to the solid curve, but the temperature level at which thetemporary pause in the temperature increase occurs is at a highertemperature of 105 degrees Celsius.

The dashed curve in FIG. 11 represents the heating curve of a capsulethat includes or is thermally coupled to a combination of a plurality ofdifferent phase-change materials, in accordance with some applicationsof the present invention. For some applications, the phase-changematerials are mixed with each other, or are thermally coupled to eachother without being mixed. The dashed curve of FIG. 11 shows an examplein which three phase-change materials are used, the materials havingphase-change transition temperatures of 65, 85 and 105 degrees Celsius.The heating curve of the capsule is generally similar to that describedwith reference to the solid curve, but due to the use of phase-changematerials with three different phase-change transition temperatures, theheating curve will include three pauses in the temperature increase,each one due to its respective phase-change material reaching its phasechanging temperature. By detecting the presence of a pause intemperature increase at pre-defined temperatures, information regardingthe type of capsule is coded into the capsule and read by the controlcircuitry without necessarily requiring the use of a dedicated sensorwithin vaporizing unit 21, in addition to temperature sensor 35. In thismanner, the use of a combination of phase-change materials, each with adifferent phase changing transition temperature, facilitates a codingmethod, which is used by the control circuitry for identification of theheated substance.

For some applications, the capsules are used with a phase-changetemperature of the phase-change material is higher than 50 degreesCelsius and/or lower than 150 degrees Celsius, e.g., 50 to 150 degreesCelsius, or 80 to 120 degrees Celsius. For some applications, thephase-change material is thermally coupled to the plant material. Forexample, the phase-change material may be mixed with the plant material.For some applications, sheets of the phase-change material partially orfully cover the plant material.

Reference is now made to FIG. 12A, which is a graph illustratingrespective techniques for heating plant material using a vaporizer, suchas vaporizing unit 21, in accordance with some applications of thepresent invention. The x-axis of the graph indicates time (measured inarbitrary time units), and the y-axis indicates the temperature(measured in degrees Celsius) of a capsule that contains a plantmaterial (and therefore indicates the temperature of the plant materialwithin the capsule), as described herein.

As described hereinabove, for some applications, a vaporizer (such asvaporizing unit 21) is used to vaporize active ingredients withincannabis. Cannabis typically has a vaporization temperature of 180degrees Celsius, and begins to become pyrolyzed at 220 degrees Celsius.Therefore, it is typically desirable to heat the cannabis to atemperature of between 190 degrees Celsius and 210 degrees Celsius. Theupper and lower boundaries of the desired temperature range to which toheat cannabis are denoted on the graph of FIG. 12A, by the two solidhorizontal lines at 190 degrees Celsius and 210 degrees Celsius. Furthertypically, it is desirable not to heat the cannabis to a temperaturethat is greater than the described temperature, in order to preventpyrolysis of the cannabis. Typically, when the vaporizer is used withplant materials other than cannabis (e.g., tobacco), similarconsiderations are applicable, although the desired temperature to whichthe plant material should be heated will vary depending on thecharacteristics of the plant material that is being used with thevaporizer.

One possible way of heating the plant material to the desiredtemperature is via gradual heating, as denoted by the dashed diagonalline, which shows the plant material being heated to the desiredtemperature over a period of more than 8 time units. Another possibleway to heat the plant material is via rapid heating, as denoted by thedotted curve in FIG. 12A. Typically, if the plant material is heatedrapidly, then initially there is an overshoot in the temperature towhich the plant material is heated. For example, this may be becausethere is a time lag between when the plant material reaches the desiredtemperature and when the control circuitry detects that the desiredtemperature has been reached and withholds causing further temperatureincrease of the plant material in response to the detected temperature.This is indicated in FIG. 12A, which shows that the dotted curveinitially rises above 220 degrees Celsius, before plateauing within thedesired temperature range. Due to the overshooting, some of the plantmaterial may become pyrolyzed.

In accordance with some applications of the present invention, atwo-stage heating process is applied to plant material within avaporizer, e.g., as indicated by the solid curve shown in FIG. 12A.Typically, in response to receiving a first input at the vaporizer(e.g., in response to the user pressing an ON switch on the vaporizer),the control circuitry of the vaporizer initiates a first heating step.Typically, the first heating step is a rapid heating step (e.g., aheating step in which the capsule that contains the plant material isheated at a rate of more than 50 degrees Celsius per second, or morethan 100 degrees Celsius per second). Further typically, the controlcircuitry of the vaporizer is configured to terminate the first heatingstep, by withholding causing further temperature increase of thecapsule, in response to detecting that the temperature of the capsule(which is indicative of the temperature of the plant material) hasreached a first temperature. Typically, the first temperature is lessthan 95 percent, e.g., less than 90 percent, or less than 80 percent, ofthe vaporization temperature of the plant material. For example, whenthe vaporizer is used to vaporize cannabis, the control circuitry of thevaporizer may be configured to withhold causing further temperatureincrease of the capsule, in response to detecting that the temperatureof the capsule has reached a first temperature that is less than 170degrees Celsius (e.g., less than 160 degrees Celsius), e.g., atemperature that is between 140 and 170 degrees Celsius, or between 150and 160 degrees Celsius.

By configuring the control circuitry to terminate the first, rapidheating stage as described above, even if there is overshoot, and thetemperature of the capsule rises above the temperature at which thefirst heating stage was programmed to be terminated, the temperature ofthe capsule will typically still not rise above the pyrolysistemperature of the plant material. For example, as shown in FIG. 12A,the control circuitry has been configured to withhold causing furthertemperature increase of the capsule in response to detecting that thetemperature of the capsule has reached approximately 160 degreesCelsius. Initially (at approximately 1 time unit), there is anovershoot, and the temperature of the capsule reaches approximately 180degrees Celsius. However, the temperature of the capsule then reaches aplateau of approximately 160 degrees Celsius, at about 2 time units. Forsome applications, the control circuitry of the vaporizer generates anoutput to the user to indicate that the first stage of the heating hasterminated. For example, the control circuitry may illuminate anindicator light, may cause the vaporizer to vibrate, and/or may emit anaudio signal (e.g., a beep).

Subsequently, in response to a second input to the vaporizer, thecontrol circuitry of the vaporizer initiates a second heating step(shown, on the solid curve in FIG. 12A, to begin at approximately 4 timeunits). Typically, between the end of the first stage of the heatingprocess, and the initiation of the second stage of the heating process,the control circuitry maintains the temperature of the capsule at thefirst temperature. For some applications, the second stage of theheating is initiated automatically in response to inhalation of air fromthe vaporizer by a user. Alternatively, the second stage of the heatingprocess may be initiated in response to a different input by the user(e.g., the user pressing the ON button a second time). Furtheralternatively, the second stage of the heating process may be initiatedautomatically after the first stage of heating is complete, and anindication (such as an indicator light, a vibration, and/or an audiosignal (e.g., a beep)) may be generated to indicate to the user to startinhalation when the target temperature for the second heating stage hasbeen reached.

During the second heating step, the control circuitry typically heatsthe capsule at a slower rate than during the first stage of the heatingprocess. For example, during the second stage of the heating process,the meshes of the capsules of the vaporizer may be heated at a rate ofless than 50 degrees Celsius per second, e.g., less than 40 degreesCelsius per second. As shown in FIG. 12A, during the second stage of theheating process (from 4 time units to 6 time units) the capsule isheated from approximately 160 degrees Celsius to 200 degrees Celsius.

In the second stage of the heating process, the control circuitry isconfigured to withhold causing further temperature increase of thecapsule in response to detecting that the temperature of the capsule isbetween the vaporization temperature of the plant material and thepyrolysis temperature of the plant material. For example, when thevaporizer is used to vaporize cannabis, the control circuitry of thevaporizer is configured to withhold causing further temperature increaseof the capsule, in response to detecting that the temperature of thecapsule has reached a second temperature that is more than 180 degreesCelsius (e.g., more than 190 degrees Celsius), and/or less than 220degrees Celsius (e.g., less than 210 degrees Celsius), e.g., atemperature that is between 180 and 220 degrees Celsius, or between 190and 210 degrees Celsius.

For some applications, by performing the heating in the two-stageprocess described hereinabove, one or more of the following results areachieved:

1) By terminating the first (rapid) stage of the heating in response tothe temperature of the capsule reaching less than 95 percent of thevaporization temperature, even if the heating overshoots, the plantmaterial is not pyrolyzed, since the plant material is not heated to atemperature that is greater than the pyrolysis temperature.

2) Since the second stage of the heating is performed slowly, there isnegligible overshooting in the second stage of the heating process, andtherefore the plant material does not get pyrolyzed in the second stageof the heating process.

3) Since, during the first stage of the heating, the plant material hasalready been heated to a temperature that is relatively close thevaporization temperature, even though the second stage of the heating isslow, the time that is required to heat the plant material to thevaporization temperature, from the initiation of the second heatingstage, is relatively short (e.g., less than two seconds).

4) Due to low heat conduction of the plant material, if the plantmaterial is heated rapidly, this can give rise to non-uniform heating ofthe plant material. This can cause portions of the plant material thatare near to the heating element(s) (e.g., the electrode(s)) to bepyrolyzed, and/or portions of the plant material that are further fromthe heating element(s) not to be vaporized. By withholding furtherheating of the plant material after the first temperature has beenreached, and until the second input is received, heat is able todissipate through the plant material (during the interim period betweenthe first and second heating stages) before any portion of the plantmaterial has been heated to the vaporization temperature. Furthermore,since the temperature increase during the second stage is relativelysmall, the temperature increase is able to dissipate through the plantmaterial relatively quickly. Thus, relatively uniform heating of theplant material is achieved, such that most of the active ingredientwithin the plant material is vaporized, while there is substantially nopyrolysis of the plant material.

For some applications, inhalation from the vaporizer by the user isautomatically detected by the control circuitry. After the first stageof the heating, there is typically a large difference between theambient temperature and the temperature of the capsule that contains theplant material. As described hereinabove, between the end of the firststage of the heating process, and the initiation of the second stage ofthe heating process, the control circuitry maintains the temperature ofthe capsule at the first temperature. Since there is a large differencebetween the ambient temperature and the temperature of the capsule, theenergy that is required to maintain the capsule (and the plant materialtherein) at a constant temperature is greater when the user is inhalingfrom the vaporizer than when the user is not inhaling. Therefore, forsome applications, the control circuitry detects that the user isinhaling from the vaporizer by detecting an indication of an amount ofenergy that is required to maintain the temperature of the capsule (andthe plant material therein) constant. For example, the control circuitrymay detect variations in the duty cycle that is used to heat the capsule(and the plant material therein). Alternatively or additionally, thecontrol circuitry may automatically detect that the user is inhalingfrom the vaporizer by directly detecting the temperature of the capsule.Since, after the first stage of the heating, there is a large differencebetween the ambient temperature and the temperature of the capsule,airflow through the capsule may cause a measurable change in thetemperature of the capsule. As described hereinabove, for someapplications, the second stage of the heating process is initiatedautomatically in response to detecting inhalation from the vaporizer bythe user.

For some applications, in response to detecting that no inhalation hasoccurred over a given time period (e.g., a time period of between 0.5seconds and 3 seconds), the temperature of the capsule is reduced tobelow the vaporization temperature of the plant material. For example,during use of the vaporizer, the user may stop inhaling for a given timeperiod, due to coughing, and/or due to irritation caused by the plantmaterial. By reducing the temperature to below the vaporizationtemperature, wastage of the active ingredient during this period isreduced, such that the user is able to receive the prescribed dosage ofthe active ingredient.

As indicated by the solid curve in FIG. 12A, between approximately 8time units and 10 time units the control circuitry causes thetemperature of the capsule to be lowered to below the vaporizationtemperature. This may be performed in response to detecting that noinhalation has occurred over a given time period (as describedhereinabove), and/or in response to a user input (e.g., in response tothe user pressing a button). From approximately 10 time units to 13 timeunits, the capsule is heated back to the vaporization temperature. Thismay be performed in response to detecting that inhalation has resumedand/or in response to a user input (e.g., in response to the userpressing a button). Between approximately 15 time units and 17 timeunits the control circuitry again causes the temperature of the capsuleto be lowered to below the vaporization temperature. This may beperformed in response to detecting that no inhalation has occurred overa given time period, and/or in response to a user input (e.g., inresponse to the user pressing a button).

Reference is now made to FIG. 12B, which is a graph illustrating atechnique for heating plant material using a vaporizer, in accordancewith some applications of the present invention. For some applications,a three-stage (or three-step) heating process is applied to plantmaterial within a vaporizer. The second two stages of the heatingprocess are generally similar to those described with reference to thesolid curve shown in FIG. 12A. (With respect to FIG. 12B, these stagesare referred to, respectively, as the second and third heating stages.)For some applications, an additional, initial stage of heating isapplied, in order to remove humidity from the plant material, as shownin FIG. 12B. For example, when the vaporizer is being used withcannabis, the vaporizer may apply the following three heating stages tothe cannabis:

1) Heating to a first temperature that is typically more than 90 degreesCelsius (e.g., more than 100 degrees Celsius) and/or less than 120degrees Celsius (e.g., less than 110 degrees Celsius, e.g., between 90degrees Celsius and 120 degrees Celsius (or between 100 and 110 degreesCelsius). For some applications, the plant material is maintained atapproximately the first temperature (e.g., the first temperatureplus/minus 5 degrees Celsius) for a given time period, for example, inorder to remove humidity from the plant material. In FIG. 12B, the firstheating stage is shown as being initiated at approximately 28 seconds.Initially, the temperature overshoots, but then is shown to plateau atbetween approximately 95 degrees Celsius and 105 degrees Celsius. Forsome applications, the plant material is maintained at approximately thefirst temperature for a time period of more than 5 seconds, e.g.,between 5 and 60 seconds (e.g., approximately 25 seconds, as shown inFIG. 12B). Typically, the first heating step is a rapid heating step(e.g., a heating step in which the capsule that contains the plantmaterial is heated at a rate of more than 50 degrees Celsius per second,or more than 100 degrees Celsius per second). Further typically, thecontrol circuitry of the vaporizer is configured to withhold causingfurther temperature increase of the capsule, in response to detectingthat the temperature of the capsule (which is indicative of thetemperature of the plant material) has reached the first temperature.

2) Heating to a second temperature that is typically more than 140degrees Celsius (e.g., more than 150 degrees Celsius), and/or less than170 degrees Celsius (e.g., less than 160 degrees Celsius), e.g., between140 and 170 degrees Celsius (or between 150 and 160 degrees Celsius).This corresponds to the first heating stage shown by the solid curve inFIG. 12A. In FIG. 12B, this stage is shown as being initiated atapproximately 63 seconds. Initially, the temperature overshoots, butthen is shown to plateau at between approximately 145 degrees Celsiusand 155 degrees Celsius. For some applications, the plant material ismaintained at approximately the second temperature (e.g., the secondtemperature plus/minus 5 degrees Celsius) for a given time period. Forexample, the plant material may be maintained at the second temperaturefor a time period of more than 5 seconds, e.g., between 5 seconds and 7minutes.

For some applications, the plant material is maintained at approximatelythe second temperature for a time period that is sufficient to causedecarboxylation of the cannabis, i.e., to convert TetrahydrocannabinolicAcid (THCA) that is present in the cannabis to Tetrahydrocannabinol(THC), and/or to convert Cannabidiolic Acid (CBDa) to Cannabidiol (CBD).For some applications, maintaining the plant material at the secondtemperature causes the decarboxylation of the cannabis in accordancewith an article by Dussy et al., entitled “Isolation of Delta9-THCA-Afrom hemp and analytical aspects concerning the determination ofDelta9-THC in cannabis products (Forensic Sci Int. 2005 Apr. 20;149(1):3-10), which is incorporated herein by reference, and/or anarticle by Veress et al., entitled “Determination of cannabinoid acidsby high-performance liquid chromatography of their neutral derivativesformed by thermal decarboxylation: I. Study of the decarboxylationprocess in open reactors” (Journal of Chromatography A 520:339-347,November 1990), which is incorporated herein by reference. For example,FIG. 12B shows the plant material being maintained at approximately thesecond temperature for approximately 25 seconds.

Typically, the second heating step is a rapid heating step (e.g., aheating step in which the capsule that contains the plant material isheated at a rate of more than 50 degrees Celsius per second, or morethan 100 degrees Celsius per second). Further typically, the controlcircuitry of the vaporizer is configured to withhold causing furthertemperature increase of the capsule, in response to detecting that thetemperature of the capsule (which is indicative of the temperature ofthe plant material) has reached the second temperature.

3) Heating to a third temperature that is more than 180 degrees Celsius(e.g., more than 190 degrees Celsius), and/or less than 220 degreesCelsius (e.g., less than 210 degrees Celsius), e.g., a temperature thatis between 180 and 220 degrees Celsius, or between 190 and 210 degreesCelsius. As shown in FIG. 12B, the third stage of heating is initiatedat approximately 90 seconds and continues until approximately 155seconds.

As described hereinabove, for some applications, the third stage of theheating (which corresponds to the second heating stage shown by thesolid curve in FIG. 12A) is initiated automatically in response toinhalation of air from the vaporizer by a user. Alternatively, the thirdstage of the heating process may be initiated in response to a differentinput by the user (e.g., the user pressing the ON button a second time).Further alternatively, the third stage of the heating process may beinitiated automatically after the second stage of heating is complete,and an indication (such as an indicator light, a vibration, and/or anaudio signal (e.g., a beep)) may be generated to indicate to the user tostart inhalation when the target temperature for the third heating stagehas been reached. During the third heating stage, the control circuitrytypically heats the capsule at a slower rate than during the first andsecond stages of the heating process. For example, during the thirdstage of the heating process, the meshes of the capsules of thevaporizer may be heated at a rate of less than 50 degrees Celsius persecond, e.g., less than 40 degrees Celsius per second. In the thirdstage of the heating process, the control circuitry is configured towithhold causing further temperature increase of the capsule in responseto detecting that the temperature of the capsule is between thevaporization temperature of the plant material and the pyrolysistemperature of the plant material. For example, when the vaporizer isused to vaporize cannabis, the control circuitry of the vaporizer isconfigured to withhold causing further temperature increase of thecapsule, in response to detecting that the temperature of the capsulehas reached a third temperature that is more than 180 degrees Celsius(e.g., more than 190 degrees Celsius), and/or less than 220 degreesCelsius (e.g., less than 210 degrees Celsius), e.g., a temperature thatis between 180 and 220 degrees Celsius, or between 190 and 210 degreesCelsius.

It is noted that, although the three-stage heating process has beendescribed primarily with respect to using cannabis as the plantmaterial, the scope of the present invention includes applying athree-stage heating process to other plant materials (e.g., tobacco),mutatis mutandis. The temperatures and time periods that are used in thethree-stage heating process when applied to plant materials other thancannabis will vary, in accordance with the characteristic vaporizationtemperatures, pyrolyzation temperatures, and other chemicalcharacteristics of the plant materials.

Reference is now made to FIGS. 13, 14, 15, 16, and 17A-17E, which areschematic illustrations of a vaporizer 260 that is configured toautomatically extract a given volumetric dose of a plant material(which, as described hereinabove, contains an active ingredient) from amass 212 of the plant material that is disposed in the vaporizer (e.g.,in a receptacle 224 of the vaporizer), in accordance with someapplications of the present invention. FIG. 13 shows a three-dimensionalview of a front side the vaporizer. FIG. 14 shows a three-dimensionalexploded view of the front side of the vaporizer. FIG. 15 shows athree-dimensional view of a rear side the vaporizer, a mouthpiece 198 ofthe vaporizer having been removed. FIG. 16 shows a cross-sectional viewof the vaporizer. FIGS. 17A-E show cross-sectional views of anextraction mechanism 225 of the vaporizer, at respective stages of theoperation of the extraction mechanism.

Typically, vaporizer 260 includes a mouthpiece 198, control circuitry204, a battery 211, a user interface (e.g. activation button 262, and/orindication LED 264) and a cover 266, 203. Typically, the mass of plantmaterial contains a plurality of volumetric doses of the plant materialdisposed in a single body, and is not separated into volumetric doses(e.g., by volumetric doses being disposed inside respective, individualcapsules, as described hereinabove). For example, as shown in FIG. 18 ,which shows a cross-sectional view of receptacle 224, a cigarette 212containing the plant material may be placed inside the receptacle.

Vaporizer 260 typically includes an extraction mechanism 225. Inresponse to a user activating the extraction mechanism, the extractionmechanism is configured to extract a given volumetric dose of the plantmaterial from the mass of plant material. For example, as shown in FIGS.16 and 17A-E, the extraction mechanism may include a button 199 that iscoupled to (or integrally formed with) a pushing surface 270, a bladetip 272 being disposed at a bottom edge of the pushing surface. Forexample, a blade 220 may be coupled to the underside of an element thatdefines the pushing surface. When the button is pushed by the user (orthe extraction mechanism is activated in a different manner), thiscauses the extraction mechanism to advance the pushing surface in asingle direction (toward the left of the page, as shown in FIG. 16 ),such that during advancement of the pushing surface, the blade tip cutsoff a given volumetric dose of the material from the mass of materialand the pushing surface pushes the volumetric dose to a surface 217(which is typically a mesh), which acts as a vaporization location, asdescribed hereinabove.

As stated hereinabove, FIGS. 17A-E show cross-sectional views of anextraction mechanism 225 of the vaporizer, at respective stages of theoperation of the extraction mechanism. For some applications, pushing ofbutton 199 advances hinged wedge 214. As shown in the transition fromFIG. 17A to FIG. 17C, the advancement of the hinged wedge causes ahinged mechanism 215 to rotate about its hinge 222, which, in turn,pushes and lifts an upper surface 216 (which is typically a mesh).Typically, upper surface 216 and lower surface 217 are both configuredto act as heating surfaces, which are configured to apply heat to avolumetric dose of the plant material, as described hereinbelow. Thelifting of the upper surface causes upper surface 216 and lower surface217 to move apart from one another, thereby creating (or increasing) agap between the upper and lower surface. The opening of the gap enablespushing surface 270 to advance a volumetric dose to above the lowersurface, such that the volumetric dose is disposed between the upper andlower surfaces. Typically, advancement of a volumetric dose into the gapbetween the upper and lower surfaces causes a used volumetric dose ofthe plant material to be pushed out from above the lower surface andinto a waste receptacle 206.

Referring now to FIG. 17D, for some applications, further pushing ofbutton 199, causes wedge 214 to snap off hinged mechanism 215.Subsequently, button 199 is released by user and retracted (typically,automatically by return spring 213), which in turn retracts pushingsurface 270 to its starting position, as shown in FIG. 17E. Retractionof the pushing surface causes spring 209 to push hinged mechanism 215toward its starting position. In turn, this causes the upper and lowersurfaces to clamp the volumetric dose between the surfaces by allowingthe upper and lower surfaces to move toward one another.

Referring again to FIG. 16 , retraction of the pushing surface to itsstarting position, allows a spring 210 to push the next volumetric doseof the plant material into position to be cut by blade tip 272. For someapplications, spring 210 pushes a pushing element (not shown) againstthe underside of cigarette 212, which contains the plant material. Asdescribed hereinabove, typically, the next time that the vaporizer isused, a used volumetric dose is removed from surface 217, by the nextvolumetric dose pushing the used volumetric dose off the surface, andinto waste receptacle 206.

A heating element is configured to vaporize the at least one activeingredient of the volumetric dose of the plant material by heating theupper and lower surfaces while the volumetric dose is disposed betweenthe surfaces. Typically, surfaces 216 and 217 are meshes, which areheated using control circuitry which drives a current into the meshes,as described hereinabove. (It is noted that control circuitry 204 suchas that shown in FIG. 14 is typically housed inside the housing ofvaporizer 260.) For some applications, other techniques for heating theplant material (e.g., as described hereinabove) are used. For someapplications, a sensor is used to monitor the temperature of the plantmaterial. For example, an optical temperature sensor 208 (shown in FIG.16 ), e.g., an infrared temperature sensor as described hereinabove, maybe used. For some applications, a two-step process and/or a three-stepprocess is used for heating the plant material, as describedhereinabove. For some applications, the temperature to which the plantmaterial is heated is dynamically modified in response to a measuredindication of the airflow rate through the plant material that iscurrently being heated, in accordance with the techniques describedhereinabove. For some applications, the airflow rate may be detected bydetecting the temperature of mesh 216 and/or mesh 217, in accordancewith the techniques described hereinabove, mutatis mutandis.

While the active ingredient is being vaporized, a user typically inhalesair via a mouthpiece 198. Air enters the vaporizer 260 through anopening 219 (FIG. 15 ) and passes through the plant material asillustrated schematically by the dotted arrow in FIG. 16 . Vapor fromthe vaporized plant material is introduced into the air flow.

For some applications, button 199 is additionally configured to causethe vaporizer to operate by being pushed. For example, button 199 may beconfigured to push against an operating switch (not shown), by beingpushed, which may cause the control circuitry to heat the meshes usingtechniques as described herein.

Reference is now made to FIGS. 18, 19, 20, 21, 22A-B, 23A-B, 24A-B, 25,and 26, which are schematic illustrations of a vaporizer 226 that isconfigured to automatically extract a given volumetric dose of plantmaterial (which, as described hereinabove, contains an activeingredient) from a mass of the plant material that is disposed in thevaporizer (e.g., in a receptacle 232 of the vaporizer), in accordancewith some applications of the present invention. FIG. 18 shows athree-dimensional front view of the vaporizer. FIG. 19 shows an explodedthree-dimensional front view of the vaporizer. FIG. 20 shows across-sectional view of the vaporizer. FIG. 21 shows a three-dimensionalview of an extraction mechanism 239 of the vaporizer. FIGS. 22A and 22Bshow front and rear views of the extraction mechanism of the vaporizer,during a first stage of the operation of the extraction mechanism. FIGS.23A and 23B show front and rear views of the extraction mechanism of thevaporizer, during a second stage of the operation of the extractionmechanism. FIGS. 24A and 24B show front and rear views of the extractionmechanism of the vaporizer, during a third stage of the operation of thevaporizer. FIGS. 25 and 26 are schematic illustrations of a wipingelement 251 of the extraction mechanism.

Typically, vaporizer 226 includes a mouthpiece 235, control circuitry229, a battery (not shown), a user interface (e.g. activation button227, and/or indication LED 228), a body 233 and a cover 234. Typically,the mass of plant material contains a plurality of volumetric doses ofthe plant material disposed in a single body, and is not separated intovolumetric doses (e.g., by volumetric doses being disposed insiderespective, individual capsules, as described hereinabove). For example,as shown in FIG. 20 , which shows a cross-sectional view of receptacle232, a cigarette 236 containing the plant material may be placed insidethe receptacle.

Vaporizer 226 typically includes an extraction mechanism 239, athree-dimensional view of which is shown in FIG. 21 . In response to auser activating the extraction mechanism (e.g., by pushing button 227),the extraction mechanism is configured to extract a given volumetricdose of the plant material from the mass of plant material. For someapplications, the extraction mechanism is configured to extract thegiven volumetric dose of the plant material from the mass of plantmaterial in an automated manner, in response to a user input (e.g., inresponse to the user pushing button 227). For example, as shown in FIG.21 , the extraction mechanism may include a motor 237 and a grindingelement 238. For some applications, the grinding element is a geardriven feed screw, which is driven, by the motor, to advance whilerotating. The feed screw is typically configured to work in a similarmanner to an Archimedes screw or a transfer screw, whereby due to thegeometry of the screw, as the screw advances over a mass of plantmaterial that is pressed on to the screw, the screw grinds off plantmaterial from the mass of plant material. In response to the extractionmechanism being activated by the user, motor 237 is activated, causingthe feed screw to turn and to grind off a volumetric dose from the massof plant material 82 and to push the volumetric dose towards surface240, which is configured to act as a vaporization location, as describedhereinabove.

Extraction mechanism 239 is typically configured to advance the grindingelement along an advancement axis, in order for the grinding element togrind the plant material. Referring to FIG. 21 , for some applications,a material advancement mechanism is configured to advance the mass ofmaterial (e.g., cigarette 236) toward the advancement axis of thegrinding element, and the extraction mechanism is configured tosynchronize the advancements of the grinding element and the mass ofmaterial with one another. For example, motor 237 may be configured, viaa transmission belt to turn threaded rod 245, in synchronization withadvancing and rotating grinding element 238. Turning the threaded rodlifts platform 246, thereby applying a force to spring 243, cigaretteholder 244 and cigarette 236. The application of force to cigarette 236advances the cigarette toward the axis of advancement of the grindingelement with a predetermined force, thereby enabling the grindingelement to grind off a volumetric dose from the mass of material.

For some applications, the vaporizer includes a lower heating surface240 (e.g., a mesh), and an upper heating surface 241 (e.g., a mesh),e.g., as shown in FIG. 20 . For some applications, the extractionmechanism is configured to move the upper and lower heating surfacesapart from one another, thereby creating (or increasing) a gap betweenthe upper and lower surfaces. The opening of the gap enables grindingelement 238 to advance a volumetric dose onto the lower surface, suchthat the volumetric dose is disposed between the upper and lowersurfaces.

With reference to FIGS. 22A-B, 23A-B, and 24A-B, for some applicationsthe extraction mechanism creates (or increases) the gap between theupper and lower surfaces in the following manner. Activation of motor237 turns bevel gear 248, which in turn advances a pushrod 249, which isattached, off center, to bevel gear 248. Upper surface 241 (FIG. 20 ) isdefined by the underside of an element 253 that is hinged. As shown inFIGS. 22A-B, in an initial stage of the operation of the extractionmechanism, the upper surface is disposed closely above lower surface 240(FIG. 20 ). As shown in FIGS. 23A-B, in a second stage of the operationof the extraction mechanism, hinged element 253, which defines the uppersurface, is pushed up by a ball bearing or wheel 254 being pushedbetween a first ramp 255 (which is coupled to hinged element 253), and asecond ramp 256, which is coupled to the lower surface. This creates (orincreases) a gap between the upper and lower surfaces. As shown in FIGS.24A-B, in a third stage of the operation of the extraction mechanism,bevel gear 248 retracts pushrod 249 and ball bearing or wheel 254, whichcauses hinged element 253 to rotate, such as to cause the upper andlower surfaces to clamp the volumetric dose between the surfaces by theupper and lower surfaces moving to move toward each other. For someapplications, a spring (not shown) is configured to cause the hingedelement to rotate in the above-described manner.

Referring now to FIG. 25 and FIG. 26 , for some applications, extractionmechanism 239 of vaporizer 226 includes a wiping element 251 configuredto wipe a used volumetric dose of plant material (i.e., a dose that hasalready been heated such as to vaporize the active ingredient) that isdisposed on surface 240 and to place it in a waste receptacle 231 (shownin FIG. 22 ). As described hereinabove, for some applications,activation of motor 237 turns bevel gear 248, which in turn advancespushrod 249. For some applications, the pushrod is connected to wipingelement 251, and the advancement of the pushrod causes the wipingelement to advance over surface 240, such as to wipe the surface in theabove-described manner. For some applications, the wiping element isdisposed on an axle 258, which passes through wheel or ball bearing orwheel 254, as shown in FIG. 26 . The axle is guided by a rail 257 (shownin FIG. 24B), which is disposed above the rear side of surface 240. Therail guides the axle, and thereby guides the wiping element, along thepath illustrated by the dashed arrows in FIG. 25 . In a first stage ofthe motion of the wiping element, as the wiping element is advanced oversurface 240, the axle is guided along the lower part of rail 257. Priorto the return of the wiping element, after completion of the wipingaction and when a new volumetric dose of the plant material is disposedon surface 240, axle 258 is guided into the upper part of rail 257, byramp 256 pushing wheel or ball bearing or wheel 254 upward. This causesthe axle to move in the return direction along the upper part of rail257. In turn, this causes the wiping element to follow the upper part ofthe path marked by dashed arrow 250 (FIG. 25 ). The return of the wipingelement along the upper part of path marked by dashed arrow 250, enablesthe wiping element to be returned to its starting position by beingmoved above the newly inserted volumetric dose (which was pushed on tothe surface 240 by grinding element 238) without disturbing, or pushingback toward the grinding element, the newly inserted volumetric dose.

As described hereinabove, typically, a heating element is configured tovaporize the at least one active ingredient of the volumetric dose ofthe plant material by heating surface 240 and surface 241. The surfacesare typically meshes, which are heated using control circuitry 229,which drives an electrical current into the meshes, as describedhereinabove. (It is noted that control circuitry 229 and a batterycharging connector 230 such as that shown in FIG. 19 is typically housedinside the housing of vaporizer 226.) For some applications, othertechniques for heating the plant material (e.g., as describedhereinabove) are used. For some applications, a sensor is used tomonitor the temperature of the plant material. For example, an opticaltemperature sensor 267 (shown in FIG. 20 ), e.g., an infraredtemperature sensor as described hereinabove, may be used. For someapplications, a two-step process and/or a three-step process is used forheating the plant material, as described hereinabove. For someapplications, the temperature to which the plant material is heated isdynamically modified in response to a measured indication of the airflowrate through the plant material that is currently being heated, inaccordance with the techniques described hereinabove. For someapplications, the airflow rate is detected by detecting the temperatureof mesh 240 and/or mesh 241, in accordance with the techniques describedhereinabove, mutatis mutandis.

While the active ingredient is being vaporized, a user typically inhalesair via a mouthpiece 235. Air enters the vaporizer 226 through anopening (not shown) and passes through the plant material as illustratedby dotted arrow on FIG. 20 . Vapor from the vaporized plant material isintroduced into the air flow.

It is noted that the applications described with reference to FIGS.13-26 , in accordance with which a volumetric dose of the plant materialis extracted from a mass of the plant material, may be combined with anyof the applications described hereinabove with reference to any one ofthe other figures, mutatis mutandis. For example, optical temperaturesensing (e.g., infrared temperature sensing), a ventilation fan (such asfan 76), a two-step heating process, and/or a three-step heating processas described hereinabove, may be used with the vaporizers shown in FIGS.13-26 . In addition, for some applications, the temperature to which theplant material is heated is dynamically modified in response to ameasured indication of the airflow rate through the plant material thatis currently being heated, in accordance with the techniques describedhereinabove. For some applications, the airflow rate is detected bydetecting the temperature of heated meshes, in accordance with thetechniques described hereinabove, mutatis mutandis.

For some applications, the vaporizers described herein include one ormore of the following elements:

For some applications, the mass of plant material is cut or partiallycut to predefined volumetric doses, in order to facilitate theextraction of volumetric doses from the mass of material. For example,the mass of material may be in the form of a cigarette, and the rollingpaper of the cigarette may be perforated at predefined intervals. Thepredefined intervals at which the rolling paper of the cigarette isperforated may be configured to correspond to the height of a portion ofthe extraction mechanism that is configured to extract the volumetricdose, e.g. the height of surface 270 (shown in FIG. 16 ).

For some applications, an air pump is configured to drive air throughthe plant material at a pre-determined rate and/or volume, during theheating process,

For some applications, a high thermal mass inert material (e.g. glass,metal beads or other) is placed inside the plant material (e.g., a massof plant material, such as a cigarette), in order to facilitate heatingof the plant material.

For some applications, the vaporizer includes a thermistor.

For some applications, the meshes described herein (e.g., meshes ofheating surfaces, and or meshes of capsules) are coupled to othercomponents using ultrasonic welding or heat pressing of the mesh to theother components. For some applications, electrical conductors arecoupled to meshes that are used as heating surfaces, using ultrasonicwelding or heat pressing. For some applications, this facilitateselectrical coupling between the electrical conductors and the meshes.

Reference is now made to FIGS. 27A and 27B, which are bar charts showingthe mass of active ingredient that is released from plant material withrespective, successive puffs of vaporizer, in accordance with someapplications of the present invention. The y-axis of the bar chartsmeasures the mass of active ingredient that is released from the plantmaterial as a percentage of a given arbitrary mass. The bar charts showthe mass of active ingredient that is released from plant materialduring each of the puffs, assuming that the total airflow through thecapsule during each of the puffs is the same as each other.

FIG. 27A shows an example of the mass of active ingredient that isreleased from plant material during each of the puffs, if the capsule isheated to the same temperature during each of the puffs. As shown,during successive puffs, the mass of active ingredient that is releasedfrom plant material during successive puffs decreases, because with eachsuccessive puff, more of the active ingredient has already been releasedfrom the plant material, such that there is less of the activeingredient available to be released.

As described hereinabove, for some applications, the control circuitryaccounts for the amount of active ingredient that has already beenvaporized from the portion of the plant material that is currently beingheated (which may, for example, be a portion of the plant material thatis disposed inside a capsule). For example, in some cases, based on therates of airflow and temperatures that have already been applied to thecapsule that is currently being heated, the control circuitry maydetermine an amount of the active ingredient that has already beenvaporized. For some applications, the control circuitry determines thetarget temperature to which to heat the capsule, in response to theamount of active ingredient that has already been vaporized. Forexample, for a given airflow rate, the control circuitry may heat thecapsule to a greater temperature, the greater the amount of the activeingredient that has already been vaporized.

FIG. 27B shows an example of the mass of active ingredient that isreleased from plant material during successive puffs, in accordance withsuch applications. As shown, the mass of active ingredient that isreleased from plant material during successive puffs remains constant,because the control circuitry increases the temperature to which theplant material is heated, such as to account for the fact that, witheach successive puff, more of the active ingredient has already beenreleased from the plant material. In this manner, when the user issmoking a given portion of plant material (e.g., a given capsule), theexperience is more similar to that of smoking a combustible cigarette,in that, when smoking a combustible cigarette, for any given inhalationairflow rate, there is no (or negligible) change in the strength,flavor, and/or mouthfullness of the smoke between the beginning of thecigarette and the end of the cigarette. Similarly, by the controlcircuitry of the vaporizer accounting for the fact that, with eachsuccessive puff, more of the active ingredient has already been releasedfrom the plant material, it is the case that, for any given inhalationairflow rate, there is no (or negligible) change in the strength,flavor, and/or mouthfullness of the vapors that are generated by thevaporizer between the beginning of the use of the portion of plantmaterial (e.g., the capsule), and the end of use of the portion of plantmaterial.

In general, the scope of the present application includes combing theapparatus and methods described herein with apparatus and methodsdescribed in WO 16/147188 to Raichman, and/or US 2016/0271347 toRaichman, both of which applications are incorporated herein byreference.

There is provided, in accordance with some applications of the presentinvention, the following inventive concepts:

Inventive concept 1. Apparatus for use with a vaporizer that isconfigured vaporize an active ingredient from a material that containsthe active ingredient, the apparatus comprising:

a capsule configured to be heated by the vaporizer, the capsulecomprising:

-   -   a portion of the material that contains the active ingredient;        and    -   perforated sheets disposed around the portion of the material,        the perforated sheets defining perforations therethrough that        are such as to guide airflow through the capsule along a        predefined airflow path.        Inventive concept 2. Apparatus for use with a material that        contains an active ingredient, the apparatus comprising:

a capsule comprising:

-   -   a portion of the material that contains the active ingredient;        and    -   sheets disposed around the portion of the material; and

a vaporizer configured to receive the capsule, and to vaporize theactive ingredient by heating the portion of the material within thecapsule, the vaporizer comprising:

-   -   a perforating mechanism that is configured to perforate the        sheets prior to the plant material being heated inside the        vaporizer.        Inventive concept 3. Apparatus for use with a plurality of        capsules containing a material that contains an active        ingredient, the apparatus comprising:

a smoking device comprising:

-   -   a vaporizing unit comprising a heating element configured, while        each of the capsules is disposed at a vaporization location        within the vaporizing unit, to cause the active ingredient of        the material within the capsule to become at least partially        vaporized by individually heating the capsule; and    -   a reloading unit that:        -   is reversibly couplable to the vaporizing unit,        -   is shaped to define at least a first receptacle that is            shaped to house the plurality of capsules in a stacked            configuration, and        -   comprises a capsule-loading mechanism configured, when the            reloading unit is in a coupled state with respect to the            vaporizing unit, to individually transfer each of the            capsules from the first receptacle within the reloading unit            to the vaporization location within the vaporizing unit.            Inventive concept 4. The apparatus according to inventive            concept 3, wherein the reloading unit comprises a plurality            of reloading units, each of the reloading units being            configured for a single use, and wherein the vaporizing unit            is configured to be reversibly couplable to each the            plurality of reloading units.            Inventive concept 5. The apparatus according to inventive            concept 3, wherein the capsule-loading mechanism is            configured, by transferring a capsule from the first            receptacle within the reloading unit to the vaporization            location within the vaporizing unit, to eject a used capsule            from the vaporization location within the vaporizing unit to            outside the smoking device.            Inventive concept 6. The apparatus according to inventive            concept 3, wherein the reloading unit comprises at least one            power supply, and wherein the vaporizing unit comprises at            least one power supply, and the power supply of the            reloading unit is configured to charge the power supply of            the vaporizing unit.            Inventive concept 7. The apparatus according to any one of            inventive concepts 3-6, wherein the reloading unit is shaped            to define a second receptacle that is shaped to house the            plurality of capsules in stacked configurations, and wherein            the capsule-loading mechanism is configured, when the            reloading unit is in a coupled state with respect to the            vaporizing unit, to individually transfer each of the            capsules from the vaporization location within the            vaporizing unit to the second receptacle within the            reloading unit.            Inventive concept 8. The apparatus according to inventive            concept 7, wherein, when the reloading unit is in a coupled            state with respect to the vaporizing unit, the first and            second receptacles and the vaporization location are            configured to be linearly aligned with each other, and            wherein the capsule-reloading mechanism comprises a linear            capsule-loading mechanism, configured to move each of the            capsules by moving linearly.            Inventive concept 9. A method comprising:

coupling a vaporizing unit and a reloading unit of a smoking device toeach other,

-   -   the vaporizing unit including a vaporization location, and    -   the reloading unit being shaped to define at least a first        receptacle that is shaped to house, in a stacked configuration,        a plurality of capsules, each of the capsules including a        material that contains an active ingredient;

using a capsule-loading mechanism, individually transferring a first oneof the capsules from the first receptacle within the reloading unit tothe vaporization location within the vaporizing unit; and

when the first capsule is disposed at the vaporization location withinthe vaporizing unit, causing the active ingredient within the materialwithin the first capsule to become at least partially vaporized byindividually heating the capsule.

Inventive concept 10. The method according to inventive concept 9,wherein transferring the first one of the capsules from the firstreceptacle within the reloading unit to the vaporization location withinthe vaporizing unit comprises ejecting a used capsule from thevaporization location within the vaporizing unit to outside the smokingdevice.Inventive concept 11. The method according to inventive concept 9,wherein the reloading unit includes at least one power supply, and thevaporizing unit includes at least one power supply, the method furthercomprising, while the vaporizing unit is in a coupled state with respectto the loading unit, using the power supply of the reloading unit tocharge the power supply of the vaporizing unit.Inventive concept 12. The method according to any one of inventiveconcepts 9-11, wherein the reloading unit is shaped to define a secondreceptacle that is shaped to house the plurality of capsules in stackedconfigurations, the method further comprising using the capsule-loadingmechanism individually transferring the first capsule from vaporizationlocation within the vaporizing unit to the second receptacle within thereloading unit.Inventive concept 13. The method according to inventive concept 12,wherein coupling the vaporizing unit and the reloading unit of to eachother comprises coupling the vaporizing unit and the reloading unit ofto each other, such that the first and second receptacles and thevaporization location are linearly aligned with each other, and whereinindividually transferring the first one of the capsules from the firstreceptacle within the reloading unit to the vaporization location withinthe vaporizing unit comprises moving the capsule-loading mechanismlinearly.Inventive concept 14. Apparatus for use with a plant material thatincludes at least one active ingredient, the apparatus comprising:

a vaporizing unit comprising:

-   -   a heating element configured to vaporize the at least one active        ingredient of a portion of the plant material that is disposed        at a vaporization location within the vaporizing unit, by        heating the portion of the plant material;    -   a sensor configured to detect an indication of airflow rate        through the vaporizing unit that is generated by a user; and    -   control circuitry configured:        -   to receive the indication of the airflow rate through the            vaporizing unit from the sensor,        -   to measure an amount of heating that the portion of the            plant material has already undergone,        -   at least partially based upon the measured indication of the            airflow rate and the amount of heating that the portion of            the plant material has already undergone, to determine a            temperature to which to heat the portion of the plant            material; and        -   to drive the heating element to heat the portion of the            plant material to the determined temperature.            Inventive concept 15. A method for use with a vaporizing            unit that is configured to vaporize at least one active            ingredient of a plant material, the method comprising:

vaporizing at least one active ingredient of at least a portion of aplant material disposed in the electronic cigarette by heating theportion of the plant material;

measuring an indication of airflow rate through the vaporizing unitgenerated by a user;

measuring an amount of heating that the portion of the plant materialhas already undergone;

at least partially based upon the measured indication of the airflowrate and the amount of heating that the portion of the plant materialhas already undergone, determining a temperature to which to heat theportion of the plant material; and

heating the portion of the plant material to the determined temperature.

Inventive concept 16. A method for use with a vaporizer that vaporizesat least one active ingredient of a material, the method comprising:

detecting an indication of a temperature of the material; and

sequentially:

-   -   heating the material, in a first heating step;    -   in response to detecting an indication that the temperature of        the material is at a first temperature, withholding causing        further temperature increase of the material, and maintaining        the temperature of the material at approximately the first        temperature for more than 5 seconds;    -   further heating the material in a second heating step;    -   in response to detecting an indication that the temperature of        the material is at a second temperature that greater than the        first temperature and that is less than 95 percent of a        vaporization temperature of the active ingredient, withholding        causing further temperature increase of the material, and        maintaining the temperature of the material at approximately the        second temperature for more than 5 seconds; and    -   heating the material to the vaporization temperature of the        active ingredient, in a third heating step.        Inventive concept 17. Apparatus for use with a material that        contains an active ingredient, the apparatus comprising:

a vaporizer comprising:

-   -   a heating element configured to vaporize the at least one active        ingredient of a material by heating the material;    -   a temperature sensor configured to detect an indication of a        temperature of the material; and    -   control circuitry configured, sequentially, to:        -   drive the heating element to heat the material, in a first            heating step;        -   in response to receiving an indication from the temperature            sensor that the temperature of the material is at a first            temperature, withhold the heating element from causing            further temperature increase of the material, and            maintaining the temperature of the material at approximately            the first temperature for more than 5 seconds;        -   drive the heating element to further heat the material in a            second heating step;        -   in response to receiving an indication from the temperature            sensor that the temperature of the material is at a second            temperature that greater than the first temperature and that            is less than 95 percent of a vaporization temperature of the            active ingredient, withhold the heating element from causing            further temperature increase of the material, and            maintaining the temperature of the material at approximately            the second temperature for more than 5 seconds; and        -   drive the heating element to heat the material to the            vaporization temperature of the active ingredient, in a            third heating step.            Inventive concept 18. A method comprising:

providing a vaporizer that is configured to hold a material thatcontains at least one active ingredient;

activating a heating element within the vaporizer to cause the activeingredient within the material to become at least partially vaporized bythe heating element heating the material;

detecting an indication of a temperature of the material, using atemperature sensor; and

ventilating a space between the material and the temperature sensor,using a fan.

Inventive concept 19. Apparatus for use with a material that contains anactive ingredient, the apparatus comprising:

a vaporizer comprising:

-   -   a heating element configured to vaporize the at least one active        ingredient of a material by heating the material;    -   a temperature sensor configured to detect an indication of a        temperature of the material; and    -   a fan configured to ventilate a space between the material and        the temperature sensor.        Inventive concept 20. Apparatus comprising:

a vaporizer configured to accommodate a mass of material that containsan active ingredient, the vaporizer comprising:

-   -   upper and lower heating surfaces;    -   an extraction mechanism configured:        -   in response to being activated, to move the upper and lower            heating surfaces apart from one another, to extract a given            volumetric dose of the material from the mass of material,            and to place the volumetric dose between the upper and lower            surfaces; and        -   subsequently, to cause the upper and lower surfaces to clamp            the volumetric dose between the surfaces by allowing the            upper and lower surfaces to move toward each other; and    -   a heating element configured to vaporize the at least one active        ingredient of the volumetric dose of the material by heating the        upper and lower surfaces while the volumetric dose is clamped        between the upper and lower surfaces.        Inventive concept 21. A method comprising:

providing a vaporizer configured to accommodate a mass of material thatcontains an active ingredient, the vaporizer including upper and lowerheating surfaces, a heating element, and an extraction mechanism;

activating the extraction mechanism to:

-   -   move the upper and lower heating surfaces apart from one        another, to extract a given volumetric dose of the material from        the mass of material, and to place the volumetric dose between        the upper and lower surfaces; and    -   subsequently, to cause the upper and lower surfaces to clamp the        volumetric dose between the surfaces by allowing the upper and        lower surfaces to move toward each other; and

while the volumetric dose is clamped between the upper and lowersurfaces, to activate the heating element to vaporize the at least oneactive ingredient of the volumetric dose of the material by heating theupper and lower surfaces.

Inventive concept 22. Apparatus comprising:

a vaporizer configured to accommodate a mass of material that containsan active ingredient, the vaporizer comprising:

-   -   a surface;    -   an extraction mechanism comprising a grinding element, the        extraction mechanism being configured, in response to being        activated, to drive the grinding element to grind off a given        volumetric dose of the material from the mass of material and        place the volumetric dose upon the surface; and    -   a heating element configured to vaporize the at least one active        ingredient of the volumetric dose of the material by heating the        surface while the volumetric dose is disposed upon the surface.        Inventive concept 23. The apparatus according to inventive        concept 22, wherein:

the extraction mechanism is configured to drive the grinding element byadvancing the grinding element along an advancement axis,

the apparatus further comprises a material advancement mechanism that isconfigured to advance the mass of material toward the advancement axisof the grinding element, and

the extraction mechanism is configured to synchronize the advancementsof the grinding element and the mass of material with one another.

Inventive concept 24. A method comprising:

providing a vaporizer configured to accommodate a mass of material thatcontains an active ingredient, the vaporizer including a surface, aheating element, and an extraction mechanism that includes a grindingelement;

activating the extraction mechanism to drive the grinding element togrind off a given volumetric dose of the material from the mass ofmaterial and place the volumetric dose upon the surface; and

while the volumetric dose is disposed upon the surface, activating theheating element to vaporize the at least one active ingredient of thevolumetric dose of the material by heating the surface.

Inventive concept 25. The method according to inventive concept 24,wherein activating the extraction mechanism to drive the grindingelement to grind off a given volumetric dose of the material from themass of material comprises:

advancing the grinding element along an advancement axis;

activating a material advancement mechanism to advance the mass ofmaterial toward the advancement axis of the grinding element; and

synchronizing the advancements of the grinding element and the mass ofmaterial with one another.

Inventive concept 26. Apparatus comprising:

a vaporizer configured to accommodate a mass of material that containsan active ingredient, the vaporizer comprising:

-   -   a surface;    -   an extraction mechanism comprising a pushing surface and a blade        tip disposed at a bottom edge of the pushing surface, the        extraction mechanism being configured, in response to being        activated, to advance the pushing surface in a single direction,        such that during advancement of the pushing surface, the blade        tip cuts off a given volumetric dose of the material from the        mass of material and the pushing surface pushes the volumetric        dose onto the surface; and    -   a heating element configured to vaporize the at least one active        ingredient of the volumetric dose of the material by heating the        surface while the volumetric dose is disposed upon the surface.        Inventive concept 27. A method comprising:

providing a vaporizer configured to accommodate a mass of material thatcontains an active ingredient, the vaporizer including a surface, aheating element, and an extraction mechanism that includes a pushingsurface and a blade tip disposed at a bottom edge of the pushingsurface;

activating the extraction mechanism to advance the pushing surface in asingle direction, such that during advancement of the pushing surface,the blade tip cuts off a given volumetric dose of the material from themass of material and the pushing surface pushes the volumetric dose ontothe surface; and

while the volumetric dose is disposed upon the surface, activating theheating element to vaporize the at least one active ingredient of thevolumetric dose of the material by heating the surface.

Inventive concept 28. Apparatus comprising:

a vaporizer configured to accommodate a mass of material that containsan active ingredient, the vaporizer comprising:

-   -   a surface;    -   a wiping element; and    -   an extraction mechanism configured, in response to being        activated, to extract an unused volumetric dose of the material        from the mass of material and place the unused volumetric dose        upon the surface;    -   a heating element configured to vaporize the at least one active        ingredient of the unused volumetric dose of the material by        heating the surface while the unused volumetric dose is disposed        upon the surface,    -   the extraction mechanism being further configured, in response        to being activated, to drive the wiping element to wipe from the        surface a used volumetric dose of the material that has already        been heated.        Inventive concept 29. A method comprising:

providing a vaporizer configured to accommodate a mass of material thatcontains an active ingredient, the vaporizer including a surface, aheating element, a wiping element, and an extraction mechanism;

activating the extraction mechanism:

-   -   to extract an unused volumetric dose of the material from the        mass of material and place the unused volumetric dose upon the        surface, and    -   to thereby drive the wiping element to wipe from the surface a        volumetric dose of the material that has already been used; and

while the unused volumetric dose is disposed upon the surface,activating the heating element to vaporize the at least one activeingredient of the unused volumetric dose of the material by heating thesurface.

It will be appreciated by persons skilled in the art that the presentinvention is not limited to what has been particularly shown anddescribed hereinabove. Rather, the scope of the present inventionincludes both combinations and subcombinations of the various featuresdescribed hereinabove, as well as variations and modifications thereofthat are not in the prior art, which would occur to persons skilled inthe art upon reading the foregoing description.

The invention claimed is:
 1. A method for operating a vaporizer usingmulti-stage heating, comprising: first heating at least one plantmaterial at a first target temperature for a first duration of time, theat least one plant material including at least one constituent compound;second heating the at least one plant material at a second targettemperature for a second duration of time, the second target temperaturebeing greater than the first target temperature; and third heating theat least one plant material at a third target temperature for a thirdduration of time, the third target temperature being greater than thesecond target temperature, the third heating causing at least a partialvaporization of the at least one constituent compound.
 2. The method ofclaim 1, wherein the first heating, the second heating, or both thefirst heating and the second heating cause a decarboxylation of the atleast one plant material.
 3. The method of claim 2, wherein thedecarboxylation of the at least one plant material occurs only duringthe second heating.
 4. The method of claim 1, wherein the first heatingand the second heating are at a higher heating rate than the thirdheating.
 5. The method of claim 1, wherein the third target temperatureis between a vaporization temperature of the at least one constituentcompound and a pyrolysis temperature of the at least one plant material.6. The method of claim 1, wherein the first heating includes heating theat least one plant material to reduce a humidity of the at least oneplant material.
 7. The method of claim 1, wherein the third heatingfurther includes, initiating the third heating due to at least one of adetection of an airflow in the vaporizer, detection of a selectableaction on the vaporizer, or combinations thereof.
 8. The method of claim1, wherein the third heating further includes, providing an indicationto commence a drawing action once the at least one plant materialreaches the third target temperature.
 9. The method of claim 1, whereinthe third heating further includes, automatically initiating the thirdheating following the second duration of time.
 10. The method of claim1, wherein the first target temperature is 90 C.° or greater, the secondtarget temperature is 140 C.° or greater, and the third targettemperature is between 180 C.° and 220 C.°.
 11. The method of claim 10,wherein the first duration of time is 5 seconds to 60 seconds long, andthe second duration of time is 5 seconds to 7 minutes long.
 12. Themethod of claim 1, wherein the first heating and the second heating havea heating rate of 50 C.° per second or more, and the third heating has aheating rate of less than 50 C.° per second.
 13. The method of claim 1,further comprising: detecting classification information for the atleast one plant material; determining a multi-stage heating profilebased on the classification information; and determining characteristicsof at least one of the first heating, the second heating, the thirdheating, or combinations thereof, using the multi-stage heating profile.14. The method of claim 1, further comprising: detecting one or morephysical changes of a phase-changing material, the phase-change materialbeing heated with the at least one plant material; and determining amulti-stage heating profile based on the detecting; and determiningcharacteristics of at least one of the first heating, the secondheating, the third heating, or combinations thereof, using themulti-stage heating profile.
 15. The method of claim 1, furthercomprising: determining at least one of the first target temperature,the second target temperature, the third target temperature, the firstduration of time, the second duration of time, the third duration oftime, or combinations thereof, using a multi-stage heating profile, andwherein the multi-stage heating profile is specific to physicalcharacteristics of the at least one plant material.
 16. The method ofclaim 1, further comprising: determining at least one of a first heatingrate for the first heating, a second heating rate for the secondheating, a third heating rate for the third heating, or combinationsthereof, using a multi-stage heating profile, and wherein themulti-stage heating profile is specific to physical characteristics ofthe at least one plant material.
 17. The method of claim 1, furthercomprising: pre-heating the at least one plant material at an initialtarget temperature for an initial duration of time, the initial targettemperature being lower than the first target temperature, thepre-heating occurring before the first heating.
 18. The method of claim1, further comprising: ceasing the third heating once the at least oneplant material reaches a pyrolysis temperature for the at least oneplant material.
 19. The method of claim 1, wherein the first heatingincludes raising a temperature of the at least one plant material to afirst overshoot temperature prior to the at least one plant materialsettling the first target temperature, the first overshoot temperaturebeing greater than the first target temperature, and the second heatingincludes raising the temperature of the at least one plant material to asecond overshoot temperature prior to the at least one plant materialsettling on the second target temperature, the second overshoottemperature being greater than the second target temperature.
 20. Themethod of claim 1, further comprising: determining a multi-stage heatingprofile based at least in part on at least one indication of at leastone first airflow rate for an airflow in the vaporizer, determiningcharacteristics of at least one of the first heating, the secondheating, the third heating, or combinations thereof, using themulti-stage heating profile.